LDP Extensions for Hub and Spoke Multipoint Label Switched Path
RFC 7140

Internet Engineering Task Force (IETF)                            L. Jin
Request for Comments: 7140
Category: Standards Track                                      F. Jounay
ISSN: 2070-1721                                                Orange CH
                                                            IJ. Wijnands
                                                      Cisco Systems, Inc
                                                              N. Leymann
                                                     Deutsche Telekom AG
                                                              March 2014

    LDP Extensions for Hub and Spoke Multipoint Label Switched Path

Abstract

   This document introduces a hub and spoke multipoint (HSMP) Label
   Switched Path (LSP), which allows traffic from root to leaf through
   point-to-multipoint (P2MP) LSPs and also leaf to root along the
   reverse path.  That means traffic entering the HSMP LSP from the
   application/customer at the root node travels downstream to each leaf
   node, exactly as if it were traveling downstream along a P2MP LSP to
   each leaf node.  Upstream traffic entering the HSMP LSP at any leaf
   node travels upstream along the tree to the root, as if it were
   unicast to the root.  Direct communication among the leaf nodes is
   not allowed.

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/rfc7140.

Jin, et al.                  Standards Track                    [Page 1]
RFC 7140               LDP Extensions for HSMP LSP            March 2014

Copyright Notice

   Copyright (c) 2014 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
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Setting Up HSMP LSP with LDP  . . . . . . . . . . . . . . . .   4
     3.1.  Support for HSMP LSP Setup with LDP . . . . . . . . . . .   4
     3.2.  HSMP FEC Elements . . . . . . . . . . . . . . . . . . . .   5
     3.3.  Using the HSMP FEC Elements . . . . . . . . . . . . . . .   5
     3.4.  HSMP LSP Label Map  . . . . . . . . . . . . . . . . . . .   6
       3.4.1.  HSMP LSP Leaf Node Operation  . . . . . . . . . . . .   7
       3.4.2.  HSMP LSP Transit Node Operation . . . . . . . . . . .   7
       3.4.3.  HSMP LSP Root Node Operation  . . . . . . . . . . . .   8
     3.5.  HSMP LSP Label Withdraw . . . . . . . . . . . . . . . . .   9
       3.5.1.  HSMP Leaf Operation . . . . . . . . . . . . . . . . .   9
       3.5.2.  HSMP Transit Node Operation . . . . . . . . . . . . .   9
       3.5.3.  HSMP Root Node Operation  . . . . . . . . . . . . . .  10
     3.6.  HSMP LSP Upstream LSR Change  . . . . . . . . . . . . . .  10
     3.7.  Determining Forwarding Interface  . . . . . . . . . . . .  10
   4.  HSMP LSP on a LAN . . . . . . . . . . . . . . . . . . . . . .  11
   5.  Redundancy Considerations . . . . . . . . . . . . . . . . . .  11
   6.  Failure Detection of HSMP LSP . . . . . . . . . . . . . . . .  11
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
     8.1.  New LDP FEC Element Types . . . . . . . . . . . . . . . .  12
     8.2.  HSMP LSP Capability TLV . . . . . . . . . . . . . . . . .  13
     8.3.  New Sub-TLVs for the Target Stack TLV . . . . . . . . . .  13
   9.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  13
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  14
     10.2.  Informative References . . . . . . . . . . . . . . . . .  14

Jin, et al.                  Standards Track                    [Page 2]