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SDP for the WebRTC
draft-nandakumar-rtcweb-sdp-02

The information below is for an old version of the document.
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This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Authors Suhas Nandakumar , Cullen Fluffy Jennings
Last updated 2013-07-13
Replaced by draft-ietf-rtcweb-sdp, draft-ietf-rtcweb-sdp
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draft-nandakumar-rtcweb-sdp-02
Network Working Group                                      S. Nandakumar
Internet-Draft                                               C. Jennings
Intended status:  Informational                                    Cisco
Expires:  January 13, 2014                                 July 12, 2013

                           SDP for the WebRTC
                     draft-nandakumar-rtcweb-sdp-02

Abstract

   The Web Real-Time Communication (WebRTC) [WEBRTC] working group is
   charged to provide protocol support for direct interactive rich
   communication using audio,video and data between two peers' web
   browsers.  With in the WebRTC framework, Session Description protocol
   (SDP) [RFC4566] is used for negotiating session capabilities between
   the peers.  Such a negotiataion happens based on the SDP Offer/Answer
   exchange mechanism described in the RFC 3264 [RFC3264].

   This document serves a introductory purpose in describing the role of
   SDP for the most common WebRTC use-cases.

   This SDP examples provided in this document is still a work in
   progress, but aims to align closest to the evolving standards.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 13, 2014.

Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal

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   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  SDP and the WebRTC . . . . . . . . . . . . . . . . . . . . . .  3
   4.  Offer/Answer and the WebRTC  . . . . . . . . . . . . . . . . .  4
   5.  WebRTC Session Description Examples  . . . . . . . . . . . . .  5
     5.1.  Secure Two-Way Audio,Video and Data with RTCP Feedback . .  5
     5.2.  Secure Two-way Audio,Video,Data and remove data stream . . 11
     5.3.  Secure Two-Way Audio,Video with BUNDLE Support Unknown . . 15
     5.4.  Secure Two-Way Audio,Video w/BUNDLE Support Known  . . . . 22
     5.5.  Secure Two-Way Audio,Video w/BUNDLE Unsupported  . . . . . 26
     5.6.  Successful One Way Session with 2 Video Streams  . . . . . 30
     5.7.  Sendonly Simulcast w/2 cameras and 2 encodings per
           camera . . . . . . . . . . . . . . . . . . . . . . . . . . 34
     5.8.  Successful SVC Video Stream  . . . . . . . . . . . . . . . 40
     5.9.  Successful Simulcast Video Streams with Retransmisson  . . 44
     5.10. Successful 1-way Simulcast with 2 resolutions and RTX
           - One resolution rejected  . . . . . . . . . . . . . . . . 48
     5.11. Simulcast Video Stream with Forward Error Correction . . . 52
   6.  WebRTC <-> Legacy Interop Examples . . . . . . . . . . . . . . 56
     6.1.  Successful legacy Interop Fallaback with bundle-only . . . 56
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 61
   8.  Change Log . . . . . . . . . . . . . . . . . . . . . . . . . . 61
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 62
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 62
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 62
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 64

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1.  Introduction

   Javascript Session Exchange Protocol(JSEP) [JSEP] specifies a generic
   protocol needed to generate [RFC3264] offers and answers negotiated
   between the WebRTC peers for setting up, updating and tearing down a
   multimedia session.  For this purpose, SDP is used to construct
   [RFC3264] offers/answers for describing (media and non-media) streams
   as appropriate for recipients of a session description to participate
   in the session.

   The remainder of this document is organized as follows:  Section 3
   and 4 provides an overview of SDP and the Offer/Answer exchange
   mechanism.  Section 5 and 6 provide sample SDP usages for the most
   common WebRTC use-cases.

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT",
   "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be
   interpreted as described in [RFC2119].

3.  SDP and the WebRTC

   The purpose of this section is to provide a general overview of SDP
   and its components.  For a more in-depth understanding, the readers
   are advised to refer to [RFC4566].

   The Session Description Protocol (SDP) [RFC4566] describes multimedia
   sessions,which can be audio,video,whiteboards,fax,modem, and other
   streams.  It provides a general purpose,standard representation to
   describe various aspects of multimedia session such as media
   capabilities,transport addresses and related metadata in a transport
   agnostic manner,for the purposes of session announcement,session
   invitation and parameter negotiation.

   As of today SDP is widely used in the context of Session Initiation
   Protocol, Real-time Transport Protocol and Real-time Streaming
   Protocol.

   Below figure introduces high-level breakup of SDP into components
   that semantically describe a multimedia session,in our case,say,a
   WebRTC session [WEBRTC].  It by no means captures everything about
   SDP and hence, should be used for informational purposes only.

   [WEBRTC] proposes JavaScript application to fully control the
   signaling plane of a multimedia session as described in the JSEP

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   specification [JSEP].  JSEP provides mechanisms to create session
   characterisation and media definition information to conduct the
   session based on SDP exchanges.

   In this context,SDP serves two purposes:
      Provide grammatical structure syntatically
      Semantically convey partipant's intention and capabilities.

4.  Offer/Answer and the WebRTC

   This section introduces SDP Offer/Answer Exchange mechanism mandated
   by WebRTC for negotitating session capabilities while setting
   up,updating and tearing down a WebRTC session.  This section is
   intentionally brief in nature and interested readers are recommended
   to [RFC3264] for specific details on the protocol operation.

   The Offer/Answer [RFC3264] model specifies rule for the bilateral
   exchange of Session Description Protocol (SDP) messages for creation
   of multimedia streams.  It defines protocol with involved
   participants exchanging desired session characteristics from each
   others perspective modelled on SDP to negotiate the session between
   them.

   In the most basic form,the protocol operation begins by one of the
   participants sending an initial SDP offer describing its intent to
   start a multimedia communication session.  The participant receiving
   the offer MAY generate an SDP answer accepting the offer or it MAY
   reject the offer.  If the session is accepted the Offer/Answer model
   guarantees a common view of the multimedia session between the
   participants.

   At any time, either participant MAY generate a new SDP offer that
   updates the session in progress.

   With in the context of WebRTC, the Offer/Answer model defines the
   state-machinery for WebRTC peers to negotiate session descriptions
   between them during the initial setup stages as well as for eventual
   session updates.  Javascript Session Establishment Protocol
   specification [JSEP] for WebRTC provides the mechanism for generating
   [RFC3264] SDP offers and answers in order for both sides of the
   session to agree upon details such as list of media formats to be
   sent/received, bandwidth information, crypto parameters, transport
   parameters, for example.

   The following sections provide samples of SDP message details and
   exchanges for the most common WebRTC usecases.

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5.  WebRTC Session Description Examples

   A typical web based real-time multimedia communication session can be
   characterized as below:

      It has zero or more Audio only,Video only or Audio/Video Media
      streams
      MAY contain zero or more non-media data streams
      All the streams are secured with DTLS/SRTP
      ICE processing for NAT Traversal
      Sessions over IPv4-only, IPv6-only, dual-stack based clients.

   As mentioned earlier [WEBRTC] proposes using SDP based Offer/Answer
   model to negotiate multimedia session between peers' browsers
   Building on the concepts from the previous sections, the following
   subsections attempts to describe the usage of SDP for the most common
   WebRTC use-cases.

   In all the use-cases, Alice and Bob are assumed to be the WebRTC
   peers unless mentioned otherwise.  Pointers to appropriate RFCs and
   notes are provided, wherever necessary,against the SDP lines.

5.1.  Secure Two-Way Audio,Video and Data with RTCP Feedback

   This use-case allows two users to participate in a two-way
   communication session securely on their WebRTC enabled Web browsers.

   title WebRTC Session - 2-Way Secure Audio,Video with RTCP Feedback
   Alice->Bob: Offer(Audio:G.711,Opus,iLBC Video:H.264,VP8)
   Bob->Alice: Answer(Audio:Opus,DTMF Video:H.264)
   Alice->Bob: Two-way Opus Audio, H.264 Video
   note right of Alice
     Session also suports RTP/RTCP Mux, RTCP feedback (nack,pli)
   end note

   More specifically, this use-case demonstrates following aspects of a
   WebRTC session
      SRTP with DTLS based encryption
      RTP and RTCP Muxing
      RTCP based feedback and reduced size support
      ICE processing for NAT Traversal
      Audio Codec Offered :  PCMU, Opus, iLBC
      Audio Codec Answered :  Opus
      Video Codecs Offered:  H.264, VP8
      Video Codecs Answered:  H.264
      Data Channel Support
   The tables (5.1 and 5.2) below capture in detail, the initial SDP
   Offer and Answer messages exchanged.

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   The exact SDP parameters specified for Data-Channel is still under
   the WG discussion and is expected to be updated once the final
   decision is reached..

   +------------------------------------------+------------------------+
   | SDP Contents                             | RFC#/Notes             |
   +------------------------------------------+------------------------+
   | v=0                                      | [RFC4566]              |
   | o=alice 20518 0 IN IP4 0.0.0.0           | [RFC4566] - Session    |
   |                                          | Origin Information     |
   | s=                                       | [RFC4566]              |
   | t=0 0                                    | [RFC4566]              |
   | a=ice-ufrag:074c6550                     | [RFC5245] - Session    |
   |                                          | Level ICE parameter    |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474af08a | [RFC5245] - Session    |
   | 068                                      | Level ICE parameter    |
   | a=fingerprint:sha-1                      | [RFC5245] - Session    |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:7 | DTLS Fingerprint for   |
   | 0:9d:1f:66:79:a8:07                      | SRTP                   |
   | a=rtcp-rsize                             | [RFC5506] - Alice      |
   |                                          | intends to use reduced |
   |                                          | size RTCP for this     |
   |                                          | session                |
   | m=audio 54609 RTP/SAVPF 0 109 98         | [RFC4566]              |
   | a=msid:ma ta                             | Identifies             |
   |                                          | RTCMediaStream ID (ma) |
   |                                          | and                    |
   |                                          | RTCMediaStreamTrack ID |
   |                                          | (ta)                   |
   | c= IN IP4 24.23.204.141                  | [RFC4566]              |
   | a=rtpmap:0 PCMU/8000                     | [RFC3551] G.711 Audio  |
   |                                          | Codec                  |
   | a=rtpmap:109 opus/48000/2                | [draft-ietf-payload-rt |
   |                                          | p-opus] - Opus Codec   |
   |                                          |  48khz, 2 channels     |
   | a=ptime:20                               | [draft-ietf-payload-rt |
   |                                          | p-opus] - Opus         |
   |                                          |  packetization of 20ms |
   | a=rtpmap:98 iLBC/8000                    | [RFC3952] - Internet   |
   |                                          | Low Bitrate Codec      |
   | a=fmtp:98 mode=20                        | [RFC3952]              |
   | a=sendrecv                               | [RFC3264] - Alice can  |
   |                                          | send and recv audio    |
   | a=rtcp-mux                               | [RFC5761] - Alice can  |
   |                                          | perform RTP/RTCP       |
   |                                          | Muxing on port 54609   |
   | b=AS:64                                  | [RFC4566] - Audio      |
   |                                          | Session B/W of 64kbps  |

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   | b=RS:800                                 | [RFC3556] - RTCP b/w   |
   |                                          | allocated to active    |
   |                                          | data senders           |
   | b=RR:2400                                | [RFC3556] - RTCP b/w   |
   |                                          | allocated to receivers |
   | a=candidate:0 1 UDP 2113667327           | [RFC5245] - Host ICE   |
   | 192.168.1.4 54609 typ host               | Candidate              |
   | a=candidate:1 1 UDP 694302207            | [RFC5245] - Server     |
   | 24.23.204.141 54609 typ srflx raddr      | Reflexive ICE          |
   | 192.168.1.4 rport 54609                  | Candidate for the      |
   |                                          | above host candidate   |
   | a=candidate:0 2 UDP 2113667326           | [RFC5245] - Second     |
   | 192.168.1.4 64678 typ host               | Host Candidate         |
   | a=candidate:1 2 UDP 1694302206           | [RFC5245] - Server     |
   | 24.23.204.141 64678 typ srflx raddr      | Reflexive Candidate    |
   | 192.168.1.4 rport 64678                  | for the Second Host    |
   |                                          | Candidate              |
   | a=rtcp-fb:109 nack                       | [RFC5104] - Indicates  |
   |                                          | NACK RTCP feedback     |
   |                                          | support                |
   | m=video 62537 RTP/SAVPF 99 120           | [RFC4566]              |
   | a=msid:ma tb                             | Identifies             |
   |                                          | RTCMediaStream ID (ma) |
   |                                          | and                    |
   |                                          | RTCMediaStreamTrack ID |
   |                                          | (tb)                   |
   | c= IN IP4 24.23.204.141                  | [RFC4566]              |
   | a=rtpmap:99 H264/90000                   | [RFC3984] - H.264      |
   |                                          | Video Codec            |
   | a=fmtp:99                                | [RFC3984]              |
   | profile-level-id=4d0028;packetization-mo |                        |
   | de=1                                     |                        |
   | a=rtpmap:120 VP8/90000                   | [draft-ietf-payload-vp |
   |                                          | 8] - VP8 video codec   |
   | a=sendrecv                               | [RFC3264] - Alice can  |
   |                                          | send and recv video    |
   | a=rtcp-mux                               | [RFC5761] - Alice can  |
   |                                          | perform RTP/RTCP       |
   |                                          | Muxing on port 62537   |
   | b=AS:256                                 | [RFC4566] - Audio      |
   |                                          | Session B/W of 256kbps |
   | b=RS:800                                 | [RFC3556] - RTCP b/w   |
   |                                          | allocated to active    |
   |                                          | data senders           |
   | b=RR:2400                                | [RFC3556] - RTCP b/w   |
   |                                          | allocated to receivers |
   | a=candidate:0 1 UDP 2113667327           | [RFC5245]              |
   | 192.168.1.4 62537 typ host               |                        |

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   | a=candidate:1 1 UDP 1694302207           | [RFC5245]              |
   | 24.23.204.141 62537 typ srflx raddr      |                        |
   | 192.168.1.4 rport 62537                  |                        |
   | a=candidate:0 2 2113667326 192.168.1.4   | [RFC5245]              |
   | 54721 typ host                           |                        |
   | a=candidate:1 2 UDP 1694302206           | [RFC5245]              |
   | 24.23.204.141 54721 typ srflx raddr      |                        |
   | 192.168.1.4 rport 54721                  |                        |
   | a=rtcp-fb:99 nack pli                    | [RFC5104] - Indicates  |
   |                                          | support for Picture    |
   |                                          | loss Indication and    |
   |                                          | NACK                   |
   | a=rtcp-fb:99 ccm fir                     | [RFC5104] - Full Intra |
   |                                          | Frame Request-Codec    |
   |                                          | Control Message        |
   |                                          | support                |
   | a=rtcp-fb:120 nack pli                   | [RFC5104] - Indicates  |
   |                                          | support for Picture    |
   |                                          | loss Indication and    |
   |                                          | NACK                   |
   | a=rtcp-fb:120 ccm fir                    | [RFC5104] - Full Intra |
   |                                          | Frame Request-Codec    |
   |                                          | Control Message        |
   |                                          | support                |
   | m=application 56966 DTLS/SCTP 5000       | [draft-ietf-rtcweb-dat |
   |                                          | a-channel]             |
   | c= IN IP4 24.23.204.141                  | [RFC4566]              |
   | a=sctpmap:5000 webrtc-Datachannel 1      | [draft-ietf-mmusic-sct |
   |                                          | p-sdp] - One data      |
   |                                          |  stream of type chat   |
   | a=webrtc-Datachannel:5000                | [draft-ietf-mmusic-sct |
   | stream=1;label="channel                  | p-sdp]                 |
   | 1";subprotocol="chat";                   |                        |
   | a=sendrecv                               | [RFC3264] - Alice can  |
   |                                          | send and recv          |
   |                                          | non-media data         |
   | a=candidate:0 1 UDP 2113667327           | [RFC5245]              |
   | 192.168.1.7 56966 typ host               |                        |
   | a=candidate:1 1 UDP 1694302207           | [RFC5245]              |
   | 24.23.204.141 56966 typ srflx raddr      |                        |
   | 192.168.1.7 rport 56966                  |                        |
   | a=candidate:0 2 UDP 2113667326           | [RFC5245]              |
   | 192.168.1.7 51641 typ host               |                        |
   | a=candidate:1 2 UDP 1694302206           | [RFC5245]              |
   | 24.23.204.141 51641 typ srflx raddr      |                        |
   | 192.168.1.7 rport 51641                  |                        |
   +------------------------------------------+------------------------+

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                          Table 1: 5.1 SDP Offer

   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=0                                       | [RFC4566]             |
   | o=bob 16833 0 IN IP4 0.0.0.0              | [RFC4566] - Session   |
   |                                           | Origin Information    |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:c300d85b                      | [RFC5245] - Session   |
   |                                           | Level ICE username    |
   |                                           | frag                  |
   | a=ice-pwd:de4e99bd291c325921d5d47efbabd9a | [RFC5245] - Session   |
   | 2                                         | Level ICE password    |
   | a=fingerprint:sha-1                       | [RFC5245] - Session   |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 | DTLS Fingerprint for  |
   | :9d:1f:66:79:a8:07                        | SRTP                  |
   | a=rtcp-rsize                              | [RFC5506] - Alice     |
   |                                           | intends to use        |
   |                                           | reduced size RTCP for |
   |                                           | this session          |
   | m=audio 49203 RTP/SAVPF 109               | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 98.248.92.77                    | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus] - Bob accept |
   |                                           | sonly Opus Codec      |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=sendrecv                                | [RFC3264] - Bob can   |
   |                                           | send and recv audio   |
   | a=rtcp-mux                                | [RFC5761] - Bob can   |
   |                                           | perform RTP/RTCP      |
   |                                           | Muxing on port 49203  |
   | b=AS:64                                   | [RFC4566] - Audio     |
   |                                           | Session b/w of 64kbps |
   | b=RS:800                                  | [RFC3556] - RTCP b/w  |
   |                                           | allocated to active   |
   |                                           | data senders          |
   | b=RR:2400                                 | [RFC3556] - RTCP b/w  |
   |                                           | allocated to          |
   |                                           | receivers             |

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   | a=candidate:0 1 UDP 2113667327            | [RFC5245] - Host ICE  |
   | 192.168.1.7 49203 typ host                | Candidate for Opus    |
   |                                           | Stream                |
   | a=ccandidate:1 1 UDP 1694302207           | [RFC5245] - Server    |
   | 98.248.92.77 49203 typ srflx raddr        | Reflexive ICE         |
   | 192.168.1.7 rport 49203                   | Candidate for the     |
   |                                           | above host candidate  |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245] - Second    |
   | 192.168.1.7 60065 typ host                | Host Candidate        |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245] - Server    |
   | 98.248.92.77 60065 typ srflx raddr        | Reflexive Candidate   |
   | 192.168.1.7 rport 60065                   | for the Second Host   |
   |                                           | Candidate             |
   | m=video 63130 RTP/SAVPF 99                | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |
   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=rtpmap:99 H264/90000                    | [RFC3984] - Bob       |
   |                                           | accepts H.264 Video   |
   |                                           | Codec.                |
   | a=fmtp:99                                 | [RFC3984]             |
   | profile-level-id=4d0028;packetization-mod |                       |
   | e=1                                       |                       |
   | a=sendrecv                                | [RFC3264] - Bob can   |
   |                                           | send and recv video   |
   | a=rtcp-mux                                | [RFC5761] - Bob can   |
   |                                           | perform RTP/RTCP      |
   |                                           | Muxing on port 63130  |
   | b=AS:256                                  | [RFC4566] - Audio     |
   |                                           | Session B/W of        |
   |                                           | 256kbps               |
   | b=RS:800                                  | [RFC3556] - RTCP b/w  |
   |                                           | allocated to active   |
   |                                           | data senders          |
   | b=RR:2400                                 | [RFC3556] - RTCP b/w  |
   |                                           | allocated to          |
   |                                           | receivers             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 63130 typ host                |                       |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245]             |
   | 98.248.92.77 63130 typ srflx raddr        |                       |
   | 192.168.1.7 rport 63130                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 56607 typ host                |                       |

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   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 98.248.92.77 56607 typ srflx raddr        |                       |
   | 192.168.1.7 rport 56607                   |                       |
   | a=rtcp-fb:99 nack pli                     | [RFC5104] - Indicates |
   |                                           | support for Picture   |
   |                                           | loss Indication and   |
   |                                           | NACK                  |
   | a=rtcp-fb:99 ccm fir                      | [RFC5104] - Full      |
   |                                           | Intra Frame           |
   |                                           | Request-Codec Control |
   |                                           | Message support       |
   | m=application 55700 DTLS/SCTP 5000        | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp]               |
   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=sctpmap:5000 webrtc-Datachannel 1       | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp]               |
   | a=webrtc-Datachannel:5000                 | [draft-ietf-mmusic-sc |
   | stream=1;label="channel                   | tp-sdp]               |
   | 1";subprotocol="chat";                    |                       |
   | a=sendrecv                                | [RFC3264] - Bob can   |
   |                                           | send and recv         |
   |                                           | non-media data        |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245] - Refer 4.1 |
   | 192.168.1.7 55700 typ host                | SDP Offer             |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245] Refer 4.1   |
   | 98.248.92.77 55700 typ srflx raddr        | SDP Offer             |
   | 192.168.1.7 rport 55700                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245] Refer 4.1   |
   | 192.168.1.7 58137 typ host                | SDP Offer             |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245] Refer 4.1   |
   | 98.248.92.77 58137 typ srflx raddr        | SDP Offer             |
   | 192.168.1.7 rport 581371                  |                       |
   +-------------------------------------------+-----------------------+

                          Table 2: 5.1 SDP Answer

5.2.  Secure Two-way Audio,Video,Data and remove data stream

   This scenario builds upon from the usecase in the section 5.1 It
   extends by Alice removing data-stream once the session is in
   progress.

   There is an ongoing discussion with in the working group to allow
   addition and deletion of streams using partial Offer/Answer exchanges
   based on m=lines.  Once a final decision is reached, the following
   example shall be updated to reflect the same.

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   title WebRTC Session (Audio,Video,Datachannel) - Drop Datachannel
   note right of Alice
       Alice & Bob are in a two-way audio,video and datachannel session.
       Alice decides to stop the datachannel stream
   end note
   Alice->Bob: Offer(Audio:Opus Video:VP8, Application: Drop)
   Bob->Alice: Answer(Audio:Opus Video:VP8, Application:Drop)
   Alice->Bob: Two-way Opus Audio and VP8 Video

   As a precondition, A Two-Way Audio,Video and Data Session is already
   setup.

   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=1                                       | [RFC4566] Incremented |
   |                                           | version to indicate   |
   |                                           | the update            |
   | o=alice 20519 0 IN IP4 0.0.0.0            | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:074c6550                      | [RFC5245]             |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474af08a0 | [RFC5245]             |
   | 68                                        |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | a=rtcp-rsize                              | [RFC5506]             |
   | m=audio 54609 RTP/SAVPF 0 109 98          | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:0 PCMU/8000                      | [RFC3551]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=rtpmap:98 iLBC/8000                     | [RFC3952] - Internet  |
   |                                           | Low Bitrate Codec     |
   | a=fmtp:98 mode=20                         | [RFC3952]             |
   | a=sendrecv                                | [RFC3264]             |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 54609 typ host                |                       |

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   | a=candidate:1 1 UDP 694302207             | [RFC5245]             |
   | 24.23.204.141 54609 typ srflx raddr       |                       |
   | 192.168.1.4 rport 54609                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.4 64678 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 24.23.204.141 64678 typ srflx raddr       |                       |
   | 192.168.1.4 rport 64678                   |                       |
   | a=rtcp-fb:109 nack                        | [RFC5104]             |
   | m=video 62537 RTP/SAVPF 99 120            | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:99 H264/90000                    | [RFC3984]             |
   | a=fmtp:99                                 | [RFC3984]             |
   | profile-level-id=4d0028;packetization-mod |                       |
   | e=1                                       |                       |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=sendrecv                                | [RFC3264]             |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 62537 typ host                |                       |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245]             |
   | 24.23.204.141 62537 typ srflx raddr       |                       |
   | 192.168.1.4 rport 62537                   |                       |
   | a=candidate:0 2 2113667326 192.168.1.4    | [RFC5245]             |
   | 54721 typ host                            |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 24.23.204.141 54721 typ srflx raddr       |                       |
   | 192.168.1.4 rport 54721                   |                       |
   | a=rtcp-fb:99 nack pli                     | [RFC5104]             |
   | a=rtcp-fb:99 ccm fir                      | [RFC5104]             |
   | a=rtcp-fb:120 nack pli                    | [RFC5104]             |
   | a=rtcp-fb:120 ccm fir                     | [RFC5104]             |
   | m=application 0 DTLS/SCTP 5000            | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp] - Port 0      |
   |                                           |  indicates dropping   |
   |                                           |  data stream          |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=sctmap:5000 webrtc-Datachannel 1        | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp]               |
   | a=webrtc-Datachannel:5000                 | [draft-ietf-mmusic-sc |
   | stream=1;label="channel                   | tp-sdp]               |
   | 1";subprotocol="chat";                    |                       |

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   | a=sendrecv                                | [RFC3264]             |
   +-------------------------------------------+-----------------------+

             Table 3: 5.2 SDP Updated Offer w/DataChannel Drop

   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=1                                       | [RFC4566]             |
   | o=bob 16833 0 IN IP4 0.0.0.0              | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:c300d85b                      | [RFC5245]             |
   | a=ice-pwd:de4e99bd291c325921d5d47efbabd9a | [RFC5245]             |
   | 2                                         |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | a=rtcp-rsize                              | [RFC5506]             |
   | m=audio 49203 RTP/SAVPF 109               | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 98.248.92.77                    | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=sendrecv                                | [RFC3264]             |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 49203 typ host                |                       |
   | a=ccandidate:1 1 UDP 1694302207           | [RFC5245]             |
   | 98.248.92.77 49203 typ srflx raddr        |                       |
   | 192.168.1.7 rport 49203                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 60065 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 98.248.92.77 60065 typ srflx raddr        |                       |
   | 192.168.1.7 rport 60065                   |                       |
   | m=video 63130 RTP/SAVPF 99                | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |

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   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=rtpmap:99 H264/90000                    | [RFC3984]             |
   | a=fmtp:99                                 | [RFC3984]             |
   | profile-level-id=4d0028;packetization-mod |                       |
   | e=1                                       |                       |
   | a=sendrecv                                | [RFC3264]             |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 63130 typ host                |                       |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245]             |
   | 98.248.92.77 63130 typ srflx raddr        |                       |
   | 192.168.1.7 rport 63130                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 56607 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 98.248.92.77 56607 typ srflx raddr        |                       |
   | 192.168.1.7 rport 56607                   |                       |
   | a=rtcp-fb:99 nack pli                     | [RFC5104]             |
   | a=rtcp-fb:99 ccm fir                      | [RFC5104]             |
   | m=application 0 DTLS/SCTP 5000            | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp] Bob accepts   |
   |                                           |  dropping the data    |
   |                                           |  stream               |
   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=sctpmap:5000 webrtc-Datachannel 1       | [draft-ietf-mmusic-sc |
   |                                           | tp-sdp]               |
   | a=webrtc-Datachannel:5000                 | [draft-ietf-mmusic-sc |
   | stream=1;label="channel                   | tp-sdp]               |
   | 1";subprotocol="chat";                    |                       |
   | a=sendrecv                                | [RFC3264]             |
   +-------------------------------------------+-----------------------+

                      Table 4: 5.2 SDP Updated Answer

5.3.  Secure Two-Way Audio,Video with BUNDLE Support Unknown

   This use-case demonstrates a successfull audio and video media
   streams multiplexing scenario using SDP BUNDLE negotiation framework
   [draft-ietf-mmusic-sdp-bundle-negotiation]

   Since Alice is unsure of the Bob's support for BUNDLE framework, the
   SDP example below shows
   o  An SDP Offer, in which the Alice assigns unique addresses to each
      "m=" line in the BUNDLE group, and requests the Answerer to select
      the Offerer's BUNDLE address.
   o  An SDP Answer, in which the Bob selects the BUNDLE address for the
      Offerer, and assigns its own local BUNDLE address to each "m="
      line in the BUNDLE group.

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   o  A subsequent SDP Offer from Alice, which is used to perform a
      BUNDLE Address Synchronization (BAS).
   Once the Offer/Answer exchange completes, both Alice and Bob each end
   up using single RTP Session for both the Media Streams.

title WebRTC Session - 2-Way Secure Audio,Video with BUNDLE
Alice->Bob: Offer(Audio:Opus Video:VP8) with BUNDLE support and unique addresses.
Bob->Alice: Answer(Audio:Opus Video:VP8) indicating its support for BUNDLE
Alice->Bob: Updated Offer(Audio:Opus Video:VP8) for Bundle Address Synchronzation.

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20518 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 109          | [RFC4566]                  |
   | a=mid:foo                            | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:200                             | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 62537 RTP/SAVPF 120          | [RFC4566]                  |

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   | a=mid:bar                            | [RFC5888] Video m=line     |
   |                                      | part of the Bundle group   |
   |                                      | with a unique port number  |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:22222                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 62537 typ host           |                            |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 24.23.204.141 62537 typ srflx raddr  |                            |
   | 192.168.1.4 rport 62537              |                            |
   | a=candidate:0 2 2113667326           | [RFC5245]                  |
   | 192.168.1.4 54721 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 54721 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54721              |                            |
   +--------------------------------------+----------------------------+

                      Table 5: 5.3 SDP Offer w/BUNDLE

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=bob 16833 0 IN IP4 0.0.0.0         | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:c300d85b                 | [RFC5245]                  |
   | a=ice-pwd:de4e99bd291c325921d5d47efb | [RFC5245]                  |
   | abd9a2                               |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Bob       |
   |                                      |  supports BUNDLE semantics |
   |                                      | .                          |
   | m=audio 49203 RTP/SAVPF 109          | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=mid:foo                            | [RFC5888] Audio m=line     |
   |                                      | part of the BUNDLE group   |
   | c= IN IP4 98.248.92.77               | [RFC4566]                  |
   | b=AS:200                             | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:33333                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.7 49203 typ host           |                            |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 98.248.92.77 49203 typ srflx raddr   |                            |
   | 192.168.1.7 rport 49203              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.7 60065 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 98.248.92.77 60065 typ srflx raddr   |                            |
   | 192.168.1.7 rport 60065              |                            |
   | m=video 49203 RTP/SAVPF 120          | [RFC4566]                  |

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   | a=mid:bar                            | [RFC5888] Video m=line     |
   |                                      | part of the BUNDLE group   |
   |                                      | with the port from audio   |
   |                                      | line repeated              |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | b=AS:1756                            | [RFC4566]                  |
   | c= IN IP4 98.248.92.77               | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:44444                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245] - Candidate      |
   | 192.168.1.7 49203 typ host           | lines identical with the   |
   |                                      | audio m-line.              |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 98.248.92.77 49203 typ srflx raddr   |                            |
   | 192.168.1.7 rport 49203              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.7 60065 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 98.248.92.77 60065 typ srflx raddr   |                            |
   | 192.168.1.7 rport 60065              |                            |
   +--------------------------------------+----------------------------+

                     Table 6: 5.3 SDP Answer w/BUNDLE

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20518 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation]           |
   | m=audio 54609 RTP/SAVPF 109          | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=mid:foo                            | [RFC5888] - Port number    |
   |                                      | finalized as Bundle        |
   |                                      | Address.                   |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:200                             | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 54609 RTP/SAVPF 120          | [RFC4566]                  |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |

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   | a=mid:bar                            | [RFC5888] - Same Bundle    |
   |                                      | address from the audio     |
   |                                      | m=line                     |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:22222                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245] - Candidate      |
   | 192.168.1.4 54609 typ host           | lines identical with the   |
   |                                      | audio m-line.              |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   +--------------------------------------+----------------------------+

                      Table 7: 5.3 SDP Offer for BAS

5.4.  Secure Two-Way Audio,Video w/BUNDLE Support Known

   This use-case is a successful audio and video stream multiplexing
   scenario, with Alice and Bob aware of each others support for SDP
   BUNDLE framework [draft-ietf-mmusic-sdp-bundle-negotiation].

title WebRTC Session - 2-Way Secure Audio,Video with BUNDLE Support Known
Alice->Bob: Offer(Audio:Opus Video:VP8) with identical port numbers
Bob->Alice: Answer(Audio:Opus Video:VP8) with identical port numbers
Alice->Bob: Two-way Opus Audio, H.264 Video over a single 5-tuple

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20518 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics.                |
   | m=audio 10000 RTP/SAVPF 109          | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=mid:foo                            | [RFC5888] - Audio m=line   |
   |                                      | part of BUNDLE group       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:200                             | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 10000 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 10000 typ srflx raddr  |                            |
   | 192.168.1.4 rport 10000              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 10000 RTP/SAVPF 120          | [RFC4566]                  |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | a=mid:bar                            | [RFC5888] - Video m=line   |
   |                                      | with Bundle address same   |
   |                                      | as the audio m=line        |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:1000                            | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:22222                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 10000 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 10000 typ srflx raddr  |                            |
   | 192.168.1.4 rport 10000              |                            |
   | a=candidate:0 2 2113667326           | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   +--------------------------------------+----------------------------+

                      Table 8: 5.4 SDP Offer w/BUNDLE

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=bob 16833 0 IN IP4 0.0.0.0         | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:c300d85b                 | [RFC5245]                  |
   | a=ice-pwd:de4e99bd291c325921d5d47efb | [RFC5245]                  |
   | abd9a2                               |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] - Bob     |
   |                                      |  supports BUNDLE semantics |
   |                                      | .                          |
   | m=audio 20000 RTP/SAVPF 109          | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=mid:foo                            | [RFC5888] - Audio m=line   |
   |                                      | part of the BUNDLE group   |
   | b=AS:200                             | [RFC4566]                  |
   | c= IN IP4 98.248.92.77               | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:33333                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.7 20000 typ host           |                            |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 98.248.92.77 20000 typ srflx raddr   |                            |
   | 192.168.1.7 rport 20000              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.7 60065 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 98.248.92.77 60065 typ srflx raddr   |                            |
   | 192.168.1.7 rport 60065              |                            |
   | m=video 20000 RTP/SAVPF 120          | [RFC4566]                  |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | a=mid:bar                            | [RFC5888] - Video m=line   |
   |                                      | with Bundle address same   |
   |                                      | as the audio m=line        |
   | b=AS:1000                            | [RFC4566]                  |
   | c= IN IP4 98.248.92.77               | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:44444                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.7 20000 typ host           |                            |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 98.248.92.77 20000 typ srflx raddr   |                            |
   | 192.168.1.7 rport 20000              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.7 60065 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 98.248.92.77 60065 typ srflx raddr   |                            |
   | 192.168.1.7 rport 60065              |                            |
   +--------------------------------------+----------------------------+

                     Table 9: 5.4 SDP Answer w/BUNDLE

5.5.  Secure Two-Way Audio,Video w/BUNDLE Unsupported

   This use-case illustrates SDP Offer/Answer exchange when the far-end
   (Bob) either doesn't support media bundling or doesn't want to group
   m=lines over a single 5-tuple.

   On successful Offer/Answer exchange, Alice and Bob each end up using
   separate RTP sessions for audio and video media streams respectively.

title WebRTC Session - 2-Way Secure Audio,Video with BUNDLE Unsupported
Alice->Bob: Offer(Audio:Opus Video:VP8)  with BUNDLE support, unique port numbers
Bob->Alice: Answer(Audio:Opus Video:VP8) with no BUNDLE support, unique port numbers
Alice->Bob: Two-way Opus Audio, H.264 Video over 2 different RTP sessions.

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20518 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=rtcp-rsize                         | [RFC5506]                  |
   | a=group:BUNDLE foo bar               | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 55232 RTP/SAVPF 109          | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=mid:foo                            | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:200                             | [RFC4566]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 55232 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 55232 typ srflx raddr  |                            |
   | 192.168.1.4 rport 55232              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 54332 RTP/SAVPF 120          | [RFC4566]                  |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | a=mid:bar                            | [RFC5888] Video m=line     |
   |                                      | part of the BUNDLE group   |
   |                                      | with a unique port number  |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | b=AS:1000                            | [RFC4566]                  |
   | a=rtpmap:120 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:22222                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54332 typ host           |                            |
   | a=candidate:1 1 UDP 1694302207       | [RFC5245]                  |
   | 24.23.204.141 54332 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54332              |                            |
   | a=candidate:0 2 2113667326           | [RFC5245]                  |
   | 192.168.1.4 54721 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 54721 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54721              |                            |
   +--------------------------------------+----------------------------+

                     Table 10: 5.5 SDP Offer w/BUNDLE

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   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=0                                       | [RFC4566]             |
   | o=bob 16833 0 IN IP4 0.0.0.0              | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:c300d85b                      | [RFC5245]             |
   | a=ice-pwd:de4e99bd291c325921d5d47efbabd9a | [RFC5245]             |
   | 2                                         |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | a=rtcp-rsize                              | [RFC5506]             |
   | m=audio 53214 RTP/SAVPF 109               | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | b=AS:200                                  | [RFC4566]             |
   | c= IN IP4 98.248.92.77                    | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=sendrecv                                | [RFC3264]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 53214 typ host                |                       |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245]             |
   | 98.248.92.77 53214 typ srflx raddr        |                       |
   | 192.168.1.7 rport 53214                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 60065 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 98.248.92.77 60065 typ srflx raddr        |                       |
   | 192.168.1.7 rport 60065                   |                       |
   | m=video 58679 RTP/SAVPF 120               | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |
   | b=AS:2000                                 | [RFC4566]             |
   | c= IN IP4 98.248.92.77                    | [RFC4566]             |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=sendrecv                                | [RFC3264]             |

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   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 58679 typ host                |                       |
   | a=candidate:1 1 UDP 1694302207            | [RFC5245]             |
   | 98.248.92.77 58679 typ srflx raddr        |                       |
   | 192.168.1.7 rport 58679                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 56607 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 98.248.92.77 56607 typ srflx raddr        |                       |
   | 192.168.1.7 rport 56607                   |                       |
   +-------------------------------------------+-----------------------+

                  Table 11: 5.5 SDP Answer without BUNDLE

5.6.  Successful One Way Session with 2 Video Streams

   In this scenario Alice and Bob engage in one-way multimedia session
   with Bob receiving two video streams, one corresponding to Alice's
   video and other corresponding to her presentation slides.

   title 1 Way Audio & Video w/2 Video Streams
   note right of Alice
   Alice offers 2 sendonly video streams
   one for her video feed and other for her presentation slides.
   end note
   Alice->Bob: Offer(Audio:Opus, Video1,2: VP8)
   note right of Bob
   Bob accepts Alice's offer
   end note
   Bob->Alice: Answer(Audio:Opus, Video1,2: VP8)
   Alice->Bob: One-way Opus Audio, VP8 Video
   note right of Alice
   Bob can hear Alice and see her video feed as well
   as her presentation slides.
   end note

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   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=0                                       | [RFC4566]             |
   | o=alice 20519 0 IN IP4 0.0.0.0            | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:074c6550                      | [RFC5245]             |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474af08a0 | [RFC5245]             |
   | 68                                        |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | a=rtcp-rsize                              | [RFC5506]             |
   | m=audio 54609 RTP/SAVPF 109               | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=sendonly                                | [RFC3264] - Send only |
   |                                           | audio stream          |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 54609 typ host                |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5104]             |
   | 192.168.1.4 64678 typ host                |                       |
   | m=video 62537 RTP/SAVPF 120               | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=content:speaker                         | [RFC4796] - Stream 1  |
   |                                           | for Alice's video     |
   | a=sendonly                                | [RFC3264] - Send only |
   |                                           | video stream          |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 62537 typ host                |                       |

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   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.4 54721 typ host                |                       |
   | m=video 62539 RTP/SAVPF 120               | [RFC4566]             |
   | a=msid:mb ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (mb) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=content:slides                          | [RFC4796] - Stream 2  |
   |                                           | for Alice's slides    |
   | a=sendonly                                | [RFC3264] - Send only |
   |                                           | video stream          |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 62539 typ host                |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.4 54723 typ host                |                       |
   +-------------------------------------------+-----------------------+

                          Table 12: 5.6 SDP Offer

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   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=0                                       | [RFC4566]             |
   | o=bob 16833 0 IN IP4 0.0.0.0              | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:c300d85b                      | [RFC5245]             |
   | a=ice-pwd:de4e99bd291c325921d5d47efbabd9a | [RFC5245]             |
   | 2                                         |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | a=rtcp-rsize                              | [RFC5506]             |
   | m=audio 49203 RTP/SAVPF 109               | [RFC4566]             |
   | a=msid:ma ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 98.248.92.77                    | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=recvonly                                | [RFC3264] - Receive   |
   |                                           | only audio stream     |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 49203 typ host                |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 60065 typ host                |                       |
   | m=video 63130 RTP/SAVPF 120               | [RFC4566]             |
   | a=msid:ma tb                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (ma) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (tb)               |
   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=content:speaker                         | [RFC4796] - Stream 1  |
   |                                           | for Alice's Video     |
   | a=recvonly                                | [RFC3264] - Receive   |
   |                                           | Only Video Stream 1   |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 63130 typ host                |                       |

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   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 56607 typ host                |                       |
   | m=video 63133 RTP/SAVPF 120               | [RFC4566]             |
   | a=msid:mb ta                              | Identifies            |
   |                                           | RTCMediaStream ID     |
   |                                           | (mb) and              |
   |                                           | RTCMediaStreamTrack   |
   |                                           | ID (ta)               |
   | c= IN IP4 98.248.92.771                   | [RFC4566]             |
   | a=rtpmap:120 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=content:slides                          | [RFC4796] - Stream 2  |
   |                                           | for Alice's Slides    |
   | a=recvonly                                | [RFC3264] - Receive   |
   |                                           | Only Video Stream 2   |
   | a=rtcp-mux                                | [RFC5761]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.7 63133 typ host                |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.7 56609 typ host                |                       |
   +-------------------------------------------+-----------------------+

                         Table 13: 5.6 SDP Answer

5.7.  Sendonly Simulcast w/2 cameras and 2 encodings per camera

   This SDP below shows Offer/Answer exchange with audio and two video
   streams each of which can send two different resolutions.

   One video stream supports VP8, while the other supports H.264.

   bundle-only framework is used along with BUNDLE grouping framework to
   enable multiplexing of all the 5 streams (audio stream + 4 video
   streams) over a single RTP Session.

title 1 Way Successful Simulcast
note right of Alice
Alice offers 2 sendonly video streams with 2 simulcast encodings per stream
end note
Alice->Bob: Offer(Audio:Opus,Video1:VP8,Video2:H.264) with bundle-only for video
note left of Bob
Bob accepts Alice's offer and 2 encodings per stream
end note
Alice->Bob: One-Way 1 Opus, 2 H.264 and 2 VP8 video streams.

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1 m2              | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 0 RTP/SAVPF 98 100           | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=imageattr:98 [x=1280,y=720]        | [RFC6236]Camera-1,Encoding |
   |                                      | -1 Resolution              |
   | a=fmtp:98 max-fr=30                  | [RFC4566]                  |
   | a=imageattr:100 [x=640,y=480]        | [RFC6236]                  |
   |                                      | Camera-1,Encoding-2        |
   |                                      | Resolution                 |
   | a=fmtp:100 max-fr=15                 | [RFC4566]                  |
   | a=ssrc-group:SIMULCAST 12345 45678   | [RFC5576]                  |
   | a=ssrc:12345                         | [RFC5576]                  |
   | a=ssrc:45678                         | [RFC5576]                  |
   | a=ssrc:12345 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |
   | a=ssrc:45678 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |
   | a=sendonly                           | [RFC3264] - Send only      |
   |                                      | video stream               |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   | m=video 0 RTP/SAVPF 98 100           | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | a=msid:ma tc                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tc)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m2                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=rtpmap:98 H264/90000               | [RFC3984]                  |
   | a=rtpmap:100 H264/90000              | [RFC3984]                  |
   | a=fmtp:98                            | [RFC3984]Camera-2,Encoding |
   | profile-level-id=4d0028;packetizatio | -1 Resolution              |
   | n-mode=1;max-fr=30                   |                            |

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   | a=fmtp:100                           | [RFC3984]Camera-1,Encoding |
   | profile-level-id=4d0028;packetizatio | -2 Resolution              |
   | n-mode=1;max-fr=15                   |                            |
   | a=ssrc:67890                         | [RFC5576]                  |
   | a=ssrc:56789                         | [RFC5576]                  |
   | a=ssrc-group:SIMULCAST 67890 56789   | [RFC5576]                  |
   | a=ssrc:67890 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |
   | a=ssrc:56789 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |
   | a=sendonly                           | [RFC3264] - Send only      |
   |                                      | video stream               |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                          Table 14: 5.8 SDP Offer

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:ufrag:c300d85b           | [RFC5245]                  |
   | a=ice-pwd:de4e99bd291c325921d5d47efb | [RFC5245]                  |
   | abd9a2                               |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1 m2              | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |

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   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:22222                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 54609 RTP/SAVPF 98 100       | BUNDLE accepted with port  |
   |                                      | repeated from the audio    |
   |                                      | port                       |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=imageattr:98 [x=1280,y=720]        | [RFC6236]Camera-1,Encoding |
   |                                      | -1 Resolution              |
   | a=fmtp:98 max-fr=30                  | [RFC4566]                  |
   | a=imageattr:100 [x=640,y=480]        | [RFC6236]                  |
   |                                      | Camera-1,Encoding-2        |
   |                                      | Resolution                 |
   | a=fmtp:100 max-fr=15                 | [RFC4566]                  |
   | a=ssrc-group:SIMULCAST 54321 87654   | [RFC5576]                  |
   | a=ssrc:54321                         | [RFC5576]                  |
   | a=ssrc:87654                         | [RFC5576]                  |
   | a=ssrc:54321 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |

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   | a=ssrc:87654 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |
   | a=sendonly                           | [RFC3264] - Send only      |
   |                                      | video stream               |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | a=rtcp-mux                           | [RFC5576]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   | m=video 54609 RTP/SAVPF 98 100       | BUNDLE accepted with port  |
   |                                      | repeated from the audio    |
   |                                      | port                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=msid:ma tc                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tc)                       |
   | a=mid:m2                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=rtpmap:98 H264/90000               | [RFC3984]                  |
   | a=rtpmap:10 H264/90000               | [RFC3984]                  |
   | a=fmtp:98                            | [RFC3984]Camera-2,Encoding |
   | profile-level-id=4d0028;packetizatio | -1 Resolution              |
   | n-mode=1;max-fr=30                   |                            |
   | a=fmtp:100                           | [RFC3984]Camera-1,Encoding |
   | profile-level-id=4d0028;packetizatio | -2 Resolution              |
   | n-mode=1;max-fr=15                   |                            |
   | a=ssrc:90876                         | [RFC5576]                  |
   | a=ssrc:89754                         | [RFC5576]                  |
   | a=ssrc-group:SIMULCAST 90876 89754   | [RFC5576]                  |
   | a=ssrc:90876 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |
   | a=ssrc:89754 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |

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   | a=sendonly                           | [RFC3264] - Send only      |
   |                                      | video stream               |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | a=rtcp-mux                           | [RFC5576]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                          Table 15: 5.8 SDP Anwer

5.8.  Successful SVC Video Stream

   This section shows an SDP Offer/Answer for a session with an audio
   and a single video stream.  The video stream is layered coding at 3
   different resolutions based on [RFC5583].  The video m=line shows 3
   streams with last stream (payload 100) dependent on streams with
   payload 96 and 97 for decoding.

  title 2 way SVC Video
  note right of Alice
  Alice offers 3 sendonly video stream with 3 layers of SVC
  end note
  Alice->Bob: Offer(Audio:Opus Video: H.264 SVC) bundle-only
  note left of Bob
  Bob accepts Alice's Offered Codec operation points
  end note
  Bob->Alice: Answer(Video: H.264) bundle-only
  Alice->Bob: One-Way H.264 Video with codec points as indicated by Bob.

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   +---------------------------------------+---------------------------+
   | SDP Contents                          | RFC#/Notes                |
   +---------------------------------------+---------------------------+
   | v=0                                   | [RFC4566]                 |
   | o=alice 20519 0 IN IP4 0.0.0.0        | [RFC4566]                 |
   | s=                                    | [RFC4566]                 |
   | t=0 0                                 | [RFC4566]                 |
   | a=ice-ufrag:074c6550                  | [RFC5245]                 |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474af | [RFC5245]                 |
   | 08a068                                |                           |
   | a=fingerprint:sha-1                   | [RFC5245]                 |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c |                           |
   | 7:70:9d:1f:66:79:a8:07                |                           |
   | a=group:BUNDLE m0 m1                  | [draft-ietf-mmusic-sdp-bu |
   |                                       | ndle-negotiation] Alice   |
   |                                       |  supports grouping of     |
   |                                       |  m=lines under BUNDLE     |
   |                                       |  semantics                |
   | m=audio 54609 RTP/SAVPF 0 109         | [RFC4566]                 |
   | a=msid:ma ta                          | Identifies RTCMediaStream |
   |                                       | ID (ma) and               |
   |                                       | RTCMediaStreamTrack ID    |
   |                                       | (ta)                      |
   | c= IN IP4 24.23.204.141               | [RFC4566]                 |
   | a=mid:m0                              | [RFC5888] Audio m=line    |
   |                                       | part of BUNDLE group with |
   |                                       | a unique port number      |
   | a=rtpmap:0 PCMU/8000                  | [RFC3551]                 |
   | a=rtpmap:109 opus/48000/2             | [draft-ietf-payload-rtp-o |
   |                                       | pus]                      |
   | a=ptime:20                            | [draft-ietf-payload-rtp-o |
   |                                       | pus]                      |
   | a=sendonly                            | [RFC3264]                 |
   | a=rtcp-mux                            | [RFC5761]                 |
   | a=candidate:0 1 UDP 2113667327        | [RFC5245]                 |
   | 192.168.1.4 54609 typ host            |                           |
   | a=candidate:1 1 UDP 694302207         | [RFC5245]                 |
   | 24.23.204.141 54609 typ srflx raddr   |                           |
   | 192.168.1.4 rport 54609               |                           |
   | a=candidate:0 2 UDP 2113667326        | [RFC5245]                 |
   | 192.168.1.4 64678 typ host            |                           |
   | a=candidate:1 2 UDP 1694302206        | [RFC5245]                 |
   | 24.23.204.141 64678 typ srflx raddr   |                           |
   | 192.168.1.4 rport 64678               |                           |
   | m=video 0 RTP/SAVPF 96 97 100         | bundle-only video line    |
   |                                       | with port number set to   |
   |                                       | zero                      |

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   | a=msid:ma tb                          | Identifies RTCMediaStream |
   |                                       | ID (ma) and               |
   |                                       | RTCMediaStreamTrack ID    |
   |                                       | (tc)                      |
   | c= IN IP4 24.23.204.141               | [RFC4566]                 |
   | a=mid:m1                              | [RFC5888] Audio m=line    |
   |                                       | part of BUNDLE group      |
   | a=msid:ma tb                          | Add appropriate reference |
   |                                       | when available            |
   | b=AS:2500                             | [RFC4566]                 |
   | a=rtpmap:96 H264/90000                | [RFC3984]                 |
   | a=fmtp:96                             | [RFC3984]H.264 Layer 1    |
   | profile-level-id=4d0028;packetization |                           |
   | -mode=1;max-fr=30;max-fs=8040         |                           |
   | a=rtpmap:97 H264/90000                | [RFC3984]                 |
   | a=fmtp:97                             | [RFC3984] H.264 Layer 2   |
   | profile-level-id=4d0028;packetization |                           |
   | -mode=1;max-fr=15;max-fs=1200         |                           |
   | a=rtpmap:100 H264-SVC/90000           | [RFC3984]                 |
   | a=fmtp:100                            | [RFC3984]                 |
   | profile-level-id=4d0028;packetization |                           |
   | -mode=1;max-fr=30;max-fs=8040         |                           |
   | a=depend:100 lay m1:96,97;            | [RFC5583]Layer 3          |
   |                                       | dependent on layers 1 and |
   |                                       | 2                         |
   | a=sendonly                            | [RFC3264] - Send only     |
   |                                       | video stream              |
   | a=rtcp-mux                            | [RFC5761]                 |
   | a=bundle-only                         | Add reference to unified  |
   |                                       | plan when available       |
   +---------------------------------------+---------------------------+

                     Table 16: 5.9 SDP Offer with SVC

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   +---------------------------------------+---------------------------+
   | SDP Contents                          | RFC#/Notes                |
   +---------------------------------------+---------------------------+
   | v=0                                   | [RFC4566]                 |
   | o=alice 20519 0 IN IP4 0.0.0.0        | [RFC4566]                 |
   | s=                                    | [RFC4566]                 |
   | t=0 0                                 | [RFC4566]                 |
   | a=ice-ufrag:074c6550                  | [RFC5245]                 |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474af | [RFC5245]                 |
   | 08a068                                |                           |
   | a=fingerprint:sha-1                   | [RFC5245]                 |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c |                           |
   | 7:70:9d:1f:66:79:a8:07                |                           |
   | a=group:BUNDLE m0 m1                  | [draft-ietf-mmusic-sdp-bu |
   |                                       | ndle-negotiation] Alice   |
   |                                       |  supports grouping of     |
   |                                       |  m=lines under BUNDLE     |
   |                                       |  semantics                |
   | m=audio 54609 RTP/SAVPF 0 109         | [RFC4566]                 |
   | a=msid:ma ta                          | Identifies RTCMediaStream |
   |                                       | ID (ma) and               |
   |                                       | RTCMediaStreamTrack ID    |
   |                                       | (ta)                      |
   | c= IN IP4 24.23.204.142               | [RFC4566]                 |
   | a=mid:m0                              | [RFC5888] Audio m=line    |
   |                                       | part of BUNDLE group with |
   |                                       | a unique port number      |
   | a=rtpmap:0 PCMU/8000                  | [RFC3551]                 |
   | a=rtpmap:109 opus/48000/2             | [draft-ietf-payload-rtp-o |
   |                                       | pus]                      |
   | a=ptime:20                            | [draft-ietf-payload-rtp-o |
   |                                       | pus]                      |
   | a=sendonly                            | [RFC3264]                 |
   | a=rtcp-mux                            | [RFC5761]                 |
   | a=candidate:0 1 UDP 2113667327        | [RFC5245]                 |
   | 192.168.1.5 54609 typ host            |                           |
   | a=candidate:1 1 UDP 694302207         | [RFC5245]                 |
   | 24.23.204.142 54609 typ srflx raddr   |                           |
   | 192.168.1.5 rport 54609               |                           |
   | a=candidate:0 2 UDP 2113667326        | [RFC5245]                 |
   | 192.168.1.5 64678 typ host            |                           |
   | a=candidate:1 2 UDP 1694302206        | [RFC5245]                 |
   | 24.23.204.142 64678 typ srflx raddr   |                           |
   | 192.168.1.5 rport 64678               |                           |
   | m=video 54609 RTP/SAVPF 96 100        | BUNDLE accepted Bundle    |
   |                                       | address same as audio     |
   |                                       | m=line.                   |

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   | a=msid:ma tb                          | Identifies RTCMediaStream |
   |                                       | ID (ma) and               |
   |                                       | RTCMediaStreamTrack ID    |
   |                                       | (tb)                      |
   | c= IN IP4 24.23.204.142               | [RFC4566]                 |
   | a=mid:m1                              | [RFC5888] Video m=line    |
   |                                       | part of BUNDLE group      |
   | b=AS:2500                             | [RFC4566]                 |
   | a=rtpmap:96 H264/90000                | [RFC3984]                 |
   | a=fmtp:96                             | [RFC3984]H.264 Layer 1    |
   | profile-level-id=4d0028;packetization |                           |
   | -mode=1;max-fr=30;max-fs=8040         |                           |
   | a=rtpmap:100 H264-SVC/90000           | [RFC3984]                 |
   | a=fmtp:100                            | [RFC3984]                 |
   | profile-level-id=4d0028;packetization |                           |
   | -mode=1;max-fr=30;max-fs=8040         |                           |
   | a=depend:100 lay m1:96;               | [RFC5583] Bob chooses 2   |
   |                                       | Codec Operation points    |
   | a=candidate:0 1 UDP 2113667327        | [RFC5245]                 |
   | 192.168.1.5 54609 typ host            |                           |
   | a=candidate:1 1 UDP 694302207         | [RFC5245]                 |
   | 24.23.204.142 54609 typ srflx raddr   |                           |
   | 192.168.1.5 rport 54609               |                           |
   | a=candidate:0 2 UDP 2113667326        | [RFC5245]                 |
   | 192.168.1.5 64678 typ host            |                           |
   | a=candidate:1 2 UDP 1694302206        | [RFC5245]                 |
   | 24.23.204.142 64678 typ srflx raddr   |                           |
   | 192.168.1.5 rport 64678               |                           |
   | a=recvonly                            | [RFC3264] - Receive only  |
   |                                       | video stream              |
   | a=rtcp-mux                            | [RFC5761]                 |
   | a=bundle-only                         | Add reference to unified  |
   |                                       | plan when available       |
   +---------------------------------------+---------------------------+

                     Table 17: 5.9 SDP Answer with SVC

5.9.  Successful Simulcast Video Streams with Retransmisson

   This section shows an SDP Offer/Answer exchange for a simulcast
   scenario with 2 two resolutions and has [RFC4588] style re-
   transmission flows.

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title Simulcast Streams with Retransmission
note right of Alice
Alice offers single audio and simulcasted video stream
end note
Alice->Bob: Offer(Audio:Opus Video:VP8 with 2 resolutions and RTX Stream) bundle-only
note right of Bob
Bob accepts all the streams offered by Alice
end note
Bob->Alice: Answer(Audio:Opus Video:VP8 with 2 resolutions and RTX Stream) bundle-only
note right of Alice
Successful 2 way simulcast session with associated retransmission streams
end note

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |

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   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 0 RTP/SAVPF 98 100 101 103   | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:103 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:100 max-fr=15;max-fs=1200     | [RFC4566]                  |
   | a=fmtp:101 apt=98;rtx-time=3000      | [RFC4588]                  |
   | a=fmtp:103 apt=100;rtx-time=3000     | [RFC4588]                  |
   | a=ssrc-group:SIMULCAST 12345 78990   | Simulcast group            |
   | a=ssrc-group:FID 12345 34567         | [RFC5888]                  |
   | a=ssrc-group:FID 78990 90887         | [RFC5888]                  |
   | a=ssrc:12345                         | [RFC5576]                  |
   | a=ssrc:78990                         | [RFC5576]                  |
   | a=ssrc:34567                         | [RFC5576]                  |
   | a=ssrc:90887                         | [RFC5576]                  |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                 Table 18: 5.10 SDP Offer w/Simulcast, RTX

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |

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   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.142              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:33333                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.5 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.142 54609 typ srflx raddr  |                            |
   | 192.168.1.5 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.5 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.142 64678 typ srflx raddr  |                            |
   | 192.168.1.5 rport 64678              |                            |
   | m=video 54609 RTP/SAVPF 98 100 101   | BUNDLE accepted with       |
   | 103                                  | Bundle address identical   |
   |                                      | to audio m-line            |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |

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   | c= IN IP4 24.23.204.142              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:103 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:100 max-fr=15;max-fs=1200     | [RFC4566]                  |
   | a=fmtp:101 apt=98;rtx-time=3000      | [RFC4588]                  |
   | a=fmtp:103 apt=100;rtx-time=3000     | [RFC4588]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.5 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.142 54609 typ srflx raddr  |                            |
   | 192.168.1.5 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.5 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.142 64678 typ srflx raddr  |                            |
   | 192.168.1.5 rport 64678              |                            |
   | a=ssrc-group:SIMULCAST 54321 77656   | Simulcast group            |
   | a=ssrc-group:FID 54321 88776         | [RFC5888]                  |
   | a=ssrc-group:FID 77656 12908         | [RFC5888]                  |
   | a=ssrc:54321                         | [RFC5576]                  |
   | a=ssrc:77656                         | [RFC5576]                  |
   | a=ssrc:88776                         | [RFC5576]                  |
   | a=ssrc:12908                         | [RFC5576]                  |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                Table 19: 5.10 SDP Answer w/Simulcast, RTX

5.10.  Successful 1-way Simulcast with 2 resolutions and RTX - One
       resolution rejected

   This section shows an SDP Offer/Answer exchange for a simulcast
   scenario with 2 two resolutions and has [RFC4588] style re-
   transmission flows.

   It also showcases when Bob rejects one of the Simulcast Video Stream
   which results in the rejection of the associated repair stream
   implicitly

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title Simulcast Streams with Retransmission
note right of Alice
Alice offers single audio and simulcasted video stream
end note
Alice->Bob: Offer(Audio:Opus Video:VP8 with 2 resolutions and RTX Streams) bundle-only
note right of Bob
Bob accepts one simulcast,rtx and rejects the other
end note
Bob->Alice: Answer(Audio:Opus Video:VP8 with 1 resolution and the RTX Stream) bundle-only
note right of Alice
Successful 1 way session with 1 Video Stream and the associated RTX Stream
end note

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |

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   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 0 RTP/SAVPF 98 100 101 103   | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:103 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:100 max-fr=15;max-fs=1200     | [RFC4566]                  |
   | a=fmtp:101 apt=98;rtx-time=3000      | [RFC4588]                  |
   | a=fmtp:103 apt=100;rtx-time=3000     | [RFC4588]                  |
   | a=ssrc-group:SIMULCAST 12345 78990   | Simulcast group            |
   | a=ssrc-group:FID 12345 34567         | [RFC5888]                  |
   | a=ssrc-group:FID 78990 90887         | [RFC5888]                  |
   | a=ssrc:12345                         | [RFC5576]                  |
   | a=ssrc:78990                         | [RFC5576]                  |
   | a=ssrc:34567                         | [RFC5576]                  |
   | a=ssrc:90887                         | [RFC5576]                  |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                 Table 20: 5.11 SDP Offer w/Simulcast, RTX

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.142              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=recvonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:33333                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.5 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.142 54609 typ srflx raddr  |                            |
   | 192.168.1.5 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.5 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.142 64678 typ srflx raddr  |                            |
   | 192.168.1.5 rport 64678              |                            |
   | m=video 54609 RTP/SAVPF 98 101       | BUNDLE accepted with       |
   |                                      | Bundle address identical   |
   |                                      | to audio m-line            |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.142              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:1756                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:101 apt=98;rtx-time=3000      | [RFC4588]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.5 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.142 54609 typ srflx raddr  |                            |
   | 192.168.1.5 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.5 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.142 64678 typ srflx raddr  |                            |
   | 192.168.1.5 rport 64678              |                            |
   | a=ssrc-group:FID 54321 88776         | [RFC5888]                  |
   | a=ssrc:54321                         | [RFC5576]                  |
   | a=ssrc:88776                         | [RFC5576]                  |
   | a=recvonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                  Table 21: 5.11 SDP Answer no Simulcast

5.11.  Simulcast Video Stream with Forward Error Correction

   This section shows an SDP Offer/Answer exchange for Simulcast video
   stream at two resolutions and and has [RFC5956] style FEC flows.

   On completion of Offer/Answer exchange, one audio stream, 2 simulcast
   video streams and 2 associated FEC streams are sent over a single
   5-Tuple as part of bundle-only and BUNDLE framework.

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title Simulcast Streams with Forward Error Correction
note right of Alice
Alice offers single audio and simulcasted video stream
end note
Alice->Bob: Offer(Audio:Opus Video:VP8 with 2 resolutions with FEC Streams) bundle-only
note right of Bob
Bob accepts simulcast stream as well as FEC streams
end note
Bob->Alice: Answer(Audio:Opus Video:VP8 with 2 resolutions with FEC Streams) bundle-only
note right of Alice
Successful Session with 4 video streams (Simulcast + FEC) and 1 Audio Stream

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:11111                         | [RFC5576]                  |

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   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 0 RTP/SAVPF 98 100 101 103   | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:2500                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101                         | [RFC5956]                  |
   | 1d-interleaved-parityfec/90000       |                            |
   | a=rtpmap:103                         | [RFC5956]                  |
   | 1d-interleaved-parityfec/90000       |                            |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:100 max-fr=15;max-fs=1200     | [RFC4566]                  |
   | a=fmtp:101 L=5; D=10;                | [RFC5956]                  |
   | repair-window=200000                 |                            |
   | a=fmtp:103 L=5; D=10;                | [RFC5956]                  |
   | repair-window=200000                 |                            |
   | a=ssrc-group:SIMULCAST 12345 78990   | Simulcast group            |
   | a=ssrc-group:FEC-FR 12345 34567      | [RFC5888]                  |
   | a=ssrc-group:FEC-FR 78990 90887      | [RFC5888]                  |
   | a=ssrc:12345                         | [RFC5576]                  |
   | a=ssrc:78990                         | [RFC5576]                  |
   | a=ssrc:34567                         | [RFC5576]                  |
   | a=ssrc:90887                         | [RFC5576]                  |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                         Table 22: 5.12 SDP Offer

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   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1                 | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=ssrc:33333                         | [RFC5576]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 54609 RTP/SAVPF 98 100 101   | BUNDLE accepted with       |
   | 103                                  | Bundle Address identical   |
   |                                      | to audio m=line.           |

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   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | b=AS:2500                            | [RFC4566]                  |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=rtpmap:101                         | [RFC5956]                  |
   | 1d-interleaved-parityfec/90000       |                            |
   | a=rtpmap:103                         | [RFC5956]                  |
   | 1d-interleaved-parityfec/90000       |                            |
   | a=fmtp:98 max-fr=30;max-fs=8040      | [RFC4566]                  |
   | a=fmtp:100 max-fr=15;max-fs=1200     | [RFC4566]                  |
   | a=fmtp:101 L=5; D=10;                | [RFC5956]                  |
   | repair-window=200000                 |                            |
   | a=fmtp:103 L=5; D=10;                | [RFC5956]                  |
   | repair-window=200000                 |                            |
   | a=ssrc-group:SIMULCAST 54321 77656   | Simulcast group            |
   | a=ssrc-group:FEC-FR 54321 88776      | [RFC5888]                  |
   | a=ssrc-group:FEC-FR 77656 12908      | [RFC5888]                  |
   | a=ssrc:54321                         | [RFC5576]                  |
   | a=ssrc:77656                         | [RFC5576]                  |
   | a=ssrc:88776                         | [RFC5576]                  |
   | a=ssrc:12908                         | [RFC5576]                  |
   | a=sendrecv                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                         Table 23: 5.12 SDP Offer

6.  WebRTC <-> Legacy Interop Examples

   In this section, we attempt to provide session descriptions
   showcasing inter-operability between a WebRTC end-point and a Legacy
   VOIP end-point.  The ideas included in here are not fully baked into
   the standards yet.

6.1.  Successful legacy Interop Fallaback with bundle-only

   In the scenario described below, Alice is a multi-stream capable
   WebRTC endpoint while Bob is a legacy VOIP end-point.  The SDP Offer/
   Answer exchange demonstrates successful session setup with fallback

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   to audio only stream negotiated via bundle-only framework between the
   end-points.  Specifically,
   o  Offer from Alice describes 2 cameras via 2 video m=lines with both
      marked as bundle-only.
   o  Since Bob doesnot recognize either BUNDLE mechanism or bundle-only
      attribute, he accepts only the audio stream from Alice.

title Successful 2-Way WebRTC <-> VOIP Interop
note right of Alice
Alice is a multistream capable WebRTC end-point & Bob is behind a legacy VOIP system
end note
Alice->Bob: Offer(Audio:Opus Video: 2 VP8, 2 H2.64 Streams) with bundle-only offer
note right of Alice
Alice marks both the video streams as bundle-only
end note
Bob->Alice: Answer(Audio:Opus)
note right of Bob
 Bob accepts only Audio stream since he doesn't recognize
 bundle-only streams
end note
Alice->Bob: Two-way Opus Audio

   +--------------------------------------+----------------------------+
   | SDP Contents                         | RFC#/Notes                 |
   +--------------------------------------+----------------------------+
   | v=0                                  | [RFC4566]                  |
   | o=alice 20519 0 IN IP4 0.0.0.0       | [RFC4566]                  |
   | s=                                   | [RFC4566]                  |
   | t=0 0                                | [RFC4566]                  |
   | a=ice-ufrag:074c6550                 | [RFC5245]                  |
   | a=ice-pwd:a28a397a4c3f31747d1ee3474a | [RFC5245]                  |
   | f08a068                              |                            |
   | a=fingerprint:sha-1                  | [RFC5245]                  |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9: |                            |
   | c7:70:9d:1f:66:79:a8:07              |                            |
   | a=group:BUNDLE m0 m1 m2              | [draft-ietf-mmusic-sdp-bun |
   |                                      | dle-negotiation] Alice     |
   |                                      |  supports grouping of      |
   |                                      |  m=lines under BUNDLE      |
   |                                      |  semantics                 |
   | m=audio 54609 RTP/SAVPF 0 109        | [RFC4566]                  |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m0                             | [RFC5888] Audio m=line     |
   |                                      | part of BUNDLE group with  |
   |                                      | a unique port number       |

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   | a=msid:ma ta                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (ta)                       |
   | a=rtpmap:0 PCMU/8000                 | [RFC3551]                  |
   | a=rtpmap:109 opus/48000/2            | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=ptime:20                           | [draft-ietf-payload-rtp-op |
   |                                      | us]                        |
   | a=sendonly                           | [RFC3264]                  |
   | a=rtcp-mux                           | [RFC5761]                  |
   | a=candidate:0 1 UDP 2113667327       | [RFC5245]                  |
   | 192.168.1.4 54609 typ host           |                            |
   | a=candidate:1 1 UDP 694302207        | [RFC5245]                  |
   | 24.23.204.141 54609 typ srflx raddr  |                            |
   | 192.168.1.4 rport 54609              |                            |
   | a=candidate:0 2 UDP 2113667326       | [RFC5245]                  |
   | 192.168.1.4 64678 typ host           |                            |
   | a=candidate:1 2 UDP 1694302206       | [RFC5245]                  |
   | 24.23.204.141 64678 typ srflx raddr  |                            |
   | 192.168.1.4 rport 64678              |                            |
   | m=video 0 RTP/SAVPF 98 100           | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m1                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=msid:ma tb                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tb)                       |
   | a=rtpmap:98 VP8/90000                | [draft-ietf-payload-vp8]   |
   | a=rtpmap:100 VP8/90000               | [draft-ietf-payload-vp8]   |
   | a=imageattr:98 [x=1280,y=720]        | [RFC6236]Camera-1,Encoding |
   |                                      | -1 Resolution              |
   | a=fmtp:98 max-fr=30                  | [RFC4566]                  |
   | a=imageattr:100 [x=640,y=480]        | [RFC6236]                  |
   |                                      | Camera-1,Encoding-2        |
   |                                      | Resolution                 |
   | a=fmtp:100 max-fr=15                 | [RFC4566]                  |
   | a=ssrc-group:SIMULCAST 12345 45678   | [RFC5576]                  |
   | a=ssrc:12345                         | [RFC5576]                  |
   | a=ssrc:45678                         | [RFC5576]                  |
   | a=ssrc:12345 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |

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   | a=ssrc:45678 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   | m=video 0 RTP/SAVPF 101 103          | bundle-only video line     |
   |                                      | with port number set to    |
   |                                      | zero                       |
   | c= IN IP4 24.23.204.141              | [RFC4566]                  |
   | a=mid:m2                             | [RFC5888] Video m=line     |
   |                                      | part of BUNDLE group       |
   | a=msid:ma tc                         | Identifies RTCMediaStream  |
   |                                      | ID (ma) and                |
   |                                      | RTCMediaStreamTrack ID     |
   |                                      | (tc)                       |
   | a=rtpmap:101 H264/90000              | [RFC3984]                  |
   | a=rtpmap:103 H264/90000              | [RFC3984]                  |
   | a=fmtp:101                           | [RFC3984]Camera-2,Encoding |
   | profile-level-id=4d0028;packetizatio | -1 Resolution              |
   | n-mode=1;max-fr=30                   |                            |
   | a=fmtp:100                           | [RFC3984]Camera-1,Encoding |
   | profile-level-id=4d0028;packetizatio | -2 Resolution              |
   | n-mode=1;max-fr=15                   |                            |
   | a=ssrc:67890                         | [RFC5576]                  |
   | a=ssrc:56789                         | [RFC5576]                  |
   | a=ssrc-group:SIMULCAST 67890 56789   | [RFC5576]                  |
   | a=ssrc:67890 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-1 |
   |                                      |  SSRC with Session CNAME   |
   | a=ssrc:56789 cname:axzo1278npDlAzM73 | [RFC5576]                  |
   |                                      | [draft-rescorla-avtcore-62 |
   |                                      | 22bis] Camera-1,Encoding-2 |
   |                                      |  SSRC with Session CNAME   |
   | a=bundle-only                        | Add reference to unified   |
   |                                      | plan when available        |
   +--------------------------------------+----------------------------+

                  Table 24: 6.1 SDP Simulcast bundle-only

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   +-------------------------------------------+-----------------------+
   | SDP Contents                              | RFC#/Notes            |
   +-------------------------------------------+-----------------------+
   | v=0                                       | [RFC4566]             |
   | o=alice 20519 0 IN IP4 0.0.0.0            | [RFC4566]             |
   | s=                                        | [RFC4566]             |
   | t=0 0                                     | [RFC4566]             |
   | a=ice-ufrag:ufrag:c300d85b                | [RFC5245]             |
   | a=ice-pwd:de4e99bd291c325921d5d47efbabd9a | [RFC5245]             |
   | 2                                         |                       |
   | a=fingerprint:sha-1                       | [RFC5245]             |
   | 99:41:49:83:4a:97:0e:1f:ef:6d:f7:c9:c7:70 |                       |
   | :9d:1f:66:79:a8:07                        |                       |
   | m=audio 54609 RTP/SAVPF 109               | [RFC4566]             |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:109 opus/48000/2                 | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=ptime:20                                | [draft-ietf-payload-r |
   |                                           | tp-opus]              |
   | a=sendonly                                | [RFC3264]             |
   | a=candidate:0 1 UDP 2113667327            | [RFC5245]             |
   | 192.168.1.4 54609 typ host                |                       |
   | a=candidate:1 1 UDP 694302207             | [RFC5245]             |
   | 24.23.204.141 54609 typ srflx raddr       |                       |
   | 192.168.1.4 rport 54609                   |                       |
   | a=candidate:0 2 UDP 2113667326            | [RFC5245]             |
   | 192.168.1.4 64678 typ host                |                       |
   | a=candidate:1 2 UDP 1694302206            | [RFC5245]             |
   | 24.23.204.141 64678 typ srflx raddr       |                       |
   | 192.168.1.4 rport 64678                   |                       |
   | m=video 0 RTP/SAVPF 98 100                | Bob doesn't recognize |
   |                                           | bundle-only and hence |
   |                                           | rejects the video     |
   |                                           | stream                |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:98 VP8/90000                     | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=rtpmap:100 VP8/90000                    | [draft-ietf-payload-v |
   |                                           | p8]                   |
   | a=imageattr:98 [x=1280,y=720]             | [RFC6236]Camera-1,Enc |
   |                                           | oding-1 Resolution    |
   | a=fmtp:98 max-fr=30                       | [RFC4566]             |
   | a=imageattr:100 [x=640,y=480]             | [RFC6236]             |
   |                                           | Camera-1,Encoding-2   |
   |                                           | Resolution            |
   | a=fmtp:100 max-fr=15                      | [RFC4566]             |

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   | m=video 0 RTP/SAVPF 98 100                | Bob doesn't recognize |
   |                                           | bundle-only and hence |
   |                                           | rejects the video     |
   |                                           | stream                |
   | c= IN IP4 24.23.204.141                   | [RFC4566]             |
   | a=rtpmap:101 H264/90000                   | [RFC3984]             |
   | a=rtpmap:103 H264/90000                   | [RFC3984]             |
   | a=fmtp:101                                | [RFC3984]Camera-2,Enc |
   | profile-level-id=4d0028;packetization-mod | oding-1 Resolution    |
   | e=1;max-fr=30                             |                       |
   | a=fmtp:100                                | [RFC3984]Camera-1,Enc |
   | profile-level-id=4d0028;packetization-mod | oding-2 Resolution    |
   | e=1;max-fr=15                             |                       |
   +-------------------------------------------+-----------------------+

                          Table 25: 6.2 SDP Anwer

7.  IANA Considerations

   This document requires no actions from IANA.

8.  Change Log

   [RFC EDITOR NOTE:  Please remove this section when publishing]

   Changes from draft-nandakumar-rtcweb-sdp-01
   o  Updated references to OPUS RTP Payload Specification.
   o  Updated BUNDLE examples based on the latest
      draft-ietf-mmusic-sdp-bundle-negotiation.
   o  Added examples for multiple audio and video flows based on Unified
      Plan.
   o  Added new examples for RTX and FEC streams
   o  Updated Simulcast and SVC examples

   Changes from draft-nandakumar-rtcweb-sdp-00
   o  Fixed editorial comments on the mailing list.
   o  Updated Data-channel SDP information based on
      draft-ietf-mmusic-sctp-sdp.
   o  Updated BUNDLE examples based on
      draft-ietf-mmusic-sdp-bundle-negotiation.
   o  Added examples for few more BUNDLE variants
   o  Added new examples for Simulcast and SVC

9.  References

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9.1.  Normative References

   [RFC3264]  Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model
              with Session Description Protocol (SDP)", RFC 3264,
              June 2002.

   [RFC4566]  Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
              Description Protocol", RFC 4566, July 2006.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

9.2.  Informative References

   [RFC5245]  Rosenberg, J., "Interactive Connectivity Establishment
              (ICE): A Protocol for Network Address Translator (NAT)
              Traversal for Offer/Answer Protocols", RFC 5245,
              July 2006.

   [WEBRTC]   W3C, "WebRTC 1.0: Real-time Communication Between
              Browsers",
              <http://dev.w3.org/2011/webrtc/editor/webrtc.html> .

   [JSEP]     Uberti, J. and C. Jennigs, "Javascript Session
              Establishment Protocol", draft-ietf-rtcweb-jsep-01 (work
              in progress), December 2012.

   [RFC5506]  Johansson, I., "Support for Reduced-Size Real-Time
              Transport Control Protocol (RTCP): Opportunities and
              Consequences", RFC 5506, April 2009.

   [RFC3551]  Schulzrinne, H. and S. Casner, "RTP Profile for Audio and
              Video Conferences with Minimal Control", RFC 3551,
              July 2003.

   [RFC3952]  Duric, A. and S. Andersen, "Real-time Transport Protocol
              (RTP) Payload Format for internet Low Bit Rate Codec
              (iLBC) Speech", RFC 3952, December 2004.

   [RFC4796]  Hautakorpi, J. and G. Camarillo, "The Session Description
              Protocol (SDP) Content Attribute", RFC 4796,
              February 2007.

   [RFC5761]  Perkins, C. and M. Westerlund, "Multiplexing RTP Data and
              Control Packets on a Single Port", RFC 5761, April 2010.

   [RFC3556]  Casner, S., "Session Description Protocol (SDP) Bandwidth
              Modifiers for RTP Control Protocol (RTCP) Bandwidth",

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              RFC 3556, July 2003.

   [RFC5104]  Wenger, S., Chandra, U., Westerlund, M., and B. Burman,
              "Codec Control Messages in the RTP Audio-Visual Profile
              with Feedback (AVPF)", RFC 5104, February 2008.

   [RFC4588]  Rey, J., Leon, D., Miyazaki, A., Varsa, V., and R.
              Hakenberg, "RTP Retransmission Payload Format", RFC 4588,
              July 2006.

   [RFC5956]  Begen, A., "Forward Error Correction Grouping Semantics in
              the Session Description Protocol", RFC 5956,
              September 2010.

   [RFC5888]  Camarillo, G. and H. Schulzrinne, "RTP Payload Format for
              H.264 Video", RFC 5888, June 2010.

   [RFC6236]  Johansson, I. and K. Jung, "Negotiation of Generic Image
              Attributes in the Session Description Protocol (SDP)",
              RFC 6236, May 2011.

   [draft-ietf-payload-rtp-opus]
               Spittka, J., Vos, K., and JM. Valin, "RTP Payload Format
              for Opus Speech and Audio Codec",
              draft-ietf-payload-rtp-opus-00 (work in progress),
              July 2012.

   [draft-ietf-payload-vp8]
              Westin, P., Lundin, H., Glover, M., Uberti, J., and F.
              Galligan, "RTP Payload Format for VP8 Video",
              draft-ietf-payload-vp8-05 (work in progress), August 2012.

   [RFC3984]  Wenger, S., Hannuksela, M., Stockhammer, T., Westerlund,
              M., and D. Singer, "RTP Payload Format for H.264 Video",
              RFC 3984, February 2005.

   [RFC5583]  Schierl, T. and S. Wenger, "Signaling Media Decoding
              Dependency in the Session Description Protocol (SDP)",
              RFC 5583, July 2009.

   [RFC5576]  Lennox, J., Ott, J., and T. Schierl, "Source-Specific
              Media Attributes in the Session Description Protocol
              (SDP)", RFC 5576, June 2009.

   [draft-ietf-rtcweb-data-channel]
              Jesup, R., Loreto, S., and M. Tuexen, "RTCWeb Datagram
              Connection", draft-ietf-rtcweb-data-channel-01 (work in
              progress), September 2012.

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   [draft-ietf-mmusic-sctp-sdp]
              Loreto, S. and G. Camarillo, "Stream Control Transmission
              Protocol (SCTP)-Based Media Transport in the Session
              Description Protocol (SDP)", draft-ietf-mmusic-sctp-sdp-03
              (work in progress), September 2012.

   [draft-ietf-mmusic-sdp-bundle-negotiation]
              Holmberg, C., Alvestrand, H., and C. Jennings,
              "Multiplexing Negotiation Using Session Description
              Protocol (SDP) Port Numbers",
              draft-ietf-mmusic-sdp-bundle-negotiation-04 (work in
              progress), February 2013.

   [draft-lennox-mmusic-sdp-source-selection]
              Lennox, J. and H. Schulzrinne, "Multiplexing Negotiation
              Using Session Description Protocol (SDP) Port Numbers",
              draft-lennox-mmusic-sdp-source-selection-05 (work in
              progress), October 2012.

   [draft-rescorla-avtcore-6222bis]
              Rescorla, E. and A. Begen, "Guidelines for Choosing RTP
              Control Protocol (RTCP) Canonical Names (CNAMEs)",
              draft-rescorla-avtcore-6222bis-00 (work in progress),
              October 2012.

Authors' Addresses

   Suhas Nandakumar
   Cisco
   170 West Tasman Drive
   San Jose, CA  95134
   USA

   Email:  snandaku@cisco.com

   Cullen Jennings
   Cisco
   170 West Tasman Drive
   San Jose, CA  95134
   USA

   Phone:  +1 408 421-9990
   Email:  fluffy@cisco.com

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