Coordinated Multicast Trees (CMT) for Transparent Interconnection of Lots of Links (TRILL)
RFC 7783

Document Type RFC - Proposed Standard (February 2016; No errata)
Updates RFC 6325
Last updated 2016-02-25
Replaces draft-tissa-trill-cmt
Stream IETF
Formats plain text pdf html bibtex
Stream WG state Submitted to IESG for Publication Dec 2014
Document shepherd Donald Eastlake
Shepherd write-up Show (last changed 2015-03-26)
IESG IESG state RFC 7783 (Proposed Standard)
Consensus Boilerplate Yes
Telechat date
Responsible AD Alia Atlas
Send notices to (None)
IANA IANA review state Version Changed - Review Needed
IANA action state RFC-Ed-Ack
Internet Engineering Task Force (IETF)                   T. Senevirathne
Request for Comments: 7783                                    Consultant
Updates: 6325                                                J. Pathangi
Category: Standards Track                                           Dell
ISSN: 2070-1721                                                J. Hudson
                                                                 Brocade
                                                           February 2016

                   Coordinated Multicast Trees (CMT)
        for Transparent Interconnection of Lots of Links (TRILL)

Abstract

   TRILL (Transparent Interconnection of Lots of Links) facilitates
   loop-free connectivity to non-TRILL networks via a choice of an
   Appointed Forwarder for a set of VLANs.  Appointed Forwarders provide
   VLAN-based load sharing with an active-standby model.  High-
   performance applications require an active-active load-sharing model.
   The active-active load-sharing model can be accomplished by
   representing any given non-TRILL network with a single virtual
   RBridge (also referred to as a virtual Routing Bridge or virtual
   TRILL switch).  Virtual representation of the non-TRILL network with
   a single RBridge poses serious challenges in multi-destination RPF
   (Reverse Path Forwarding) check calculations.  This document
   specifies required enhancements to build Coordinated Multicast Trees
   (CMT) within the TRILL campus to solve related RPF issues.  CMT,
   which only requires a software upgrade, provides flexibility to
   RBridges in selecting a desired path of association to a given TRILL
   multi-destination distribution tree.  This document updates RFC 6325.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7783.

Senevirathne, et al.         Standards Track                    [Page 1]
RFC 7783          Coordinated Multicast Trees for TRILL    February 2016

Copyright Notice

   Copyright (c) 2016 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
   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
      1.1. Scope and Applicability ....................................4
   2. Conventions Used in This Document ...............................5
      2.1. Acronyms and Phrases .......................................5
   3. The Affinity Sub-TLV ............................................6
   4. Multicast Tree Construction and Use of Affinity Sub-TLV .........6
      4.1. Update to RFC 6325 .........................................7
      4.2. Announcing Virtual RBridge Nickname ........................8
      4.3. Affinity Sub-TLV Capability ................................8
   5. Theory of Operation .............................................8
      5.1. Distribution Tree Assignment ...............................8
      5.2. Affinity Sub-TLV Advertisement .............................9
      5.3. Affinity Sub-TLV Conflict Resolution .......................9
      5.4. Ingress Multi-Destination Forwarding ......................10
           5.4.1. Forwarding when n < k ..............................10
      5.5. Egress Multi-Destination Forwarding .......................11
           5.5.1. Traffic Arriving on an Assigned Tree to RBk-RBv ....11
           5.5.2. Traffic Arriving on Other Trees ....................11
      5.6. Failure Scenarios .........................................11
           5.6.1. Edge RBridge RBk Failure ...........................11
      5.7. Backward Compatibility ....................................12
   6. Security Considerations ........................................13
   7. IANA Considerations ............................................13
Show full document text