STIR Out of Band Architecture and Use Cases
draft-ietf-stir-oob-00

Document Type Active Internet-Draft (stir WG)
Last updated 2017-07-05 (latest revision 2017-07-03)
Replaces draft-rescorla-stir-fallback
Stream IETF
Intended RFC status (None)
Formats plain text pdf html bibtex
Stream WG state WG Document
Document shepherd No shepherd assigned
IESG IESG state I-D Exists
Consensus Boilerplate Unknown
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                        E. Rescorla
Internet-Draft                                                   Mozilla
Intended status: Standards Track                             J. Peterson
Expires: January 4, 2018                                         Neustar
                                                            July 3, 2017

              STIR Out of Band Architecture and Use Cases
                       draft-ietf-stir-oob-00.txt

Abstract

   The PASSporT format defines a token that can be carried by signaling
   protocols, including SIP, to cryptographically attest the identify of
   callers.  Not all telephone calls use Internet signaling protocols,
   however, and some calls use them for only part of their signaling
   path.  This document describes use cases that require the delivery of
   PASSporT objects outside of the signaling path, and defines
   architectures and semantics to provide this functionality.

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 4, 2018.

Copyright Notice

   Copyright (c) 2017 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
   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

Rescorla & Peterson      Expires January 4, 2018                [Page 1]
Internet-Draft                STIR Fallback                    July 2017

   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Operating Environments  . . . . . . . . . . . . . . . . . . .   4
   4.  Dataflows . . . . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .   6
     5.1.  Case 1: VoIP to PSTN Call . . . . . . . . . . . . . . . .   6
     5.2.  Case 2: Two Smart PSTN endpoints  . . . . . . . . . . . .   6
     5.3.  Case 3: PSTN to VoIP Call . . . . . . . . . . . . . . . .   7
     5.4.  Case 4: Gateway Out-of-band . . . . . . . . . . . . . . .   7
   6.  Authorization for Storing and Retrieving PASSporTs  . . . . .   8
     6.1.  Storage . . . . . . . . . . . . . . . . . . . . . . . . .   8
     6.2.  Retrieval . . . . . . . . . . . . . . . . . . . . . . . .   9
       6.2.1.  Authentication  . . . . . . . . . . . . . . . . . . .  10
       6.2.2.  Encryption  . . . . . . . . . . . . . . . . . . . . .  10
   7.  Solution Architecture . . . . . . . . . . . . . . . . . . . .  12
     7.1.  Credentials and Phone Numbers . . . . . . . . . . . . . .  12
     7.2.  Solution Architecture . . . . . . . . . . . . . . . . . .  12
     7.3.  Security Analysis . . . . . . . . . . . . . . . . . . . .  13
     7.4.  Substitution Attacks  . . . . . . . . . . . . . . . . . .  14
   8.  Call Placement Service Discovery  . . . . . . . . . . . . . .  15
   9.  To Do . . . . . . . . . . . . . . . . . . . . . . . . . . . .  16
     9.1.  Credential Lookup . . . . . . . . . . . . . . . . . . . .  16
   10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  17
   11. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  17
   12. Security Considerations . . . . . . . . . . . . . . . . . . .  17
   13. Informative References  . . . . . . . . . . . . . . . . . . .  17
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  18

1.  Introduction

   The STIR problem statement [RFC7340] describes widespread problems
   enabled by impersonation in the telephone network, including illegal
   robocalling, voicemail hacking, and swatting.  As telephone services
   are increasingly migrating onto the Internet, and using Voice over IP
Show full document text