Preferred Path Route Graph Structure
draft-ce-lsr-ppr-graph-01

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 00
• 01

LSR Working Group                                            U. Chunduri
Internet-Draft                                                 T. Eckert
Intended status: Standards Track                              Huawei USA
Expires: April 26, 2019                                 October 23, 2018

                  Preferred Path Route Graph Structure
                       draft-ce-lsr-ppr-graph-01

Abstract

   This document defines a graph structure for the Preferred Path Route
   (PPR) for IS-IS, OSPFv2 and OSPFv3 protocols.  This structure helps
   further scale of the PPR and reduce domain level global entries
   needed in some data planes.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC2119 [RFC2119],
   RFC8174 [RFC8174] when, and only when they appear in all capitals, as
   shown here.

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 https://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 April 26, 2019.

Copyright Notice

   Copyright (c) 2018 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

Chunduri & Eckert        Expires April 26, 2019                 [Page 1]
Internet-Draft    Preferred Path Route Graph Structure      October 2018

   (https://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  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Acronyms  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  PPR Graph TLVs  . . . . . . . . . . . . . . . . . . . . . . .   4
     2.1.  IS-IS TLVs  . . . . . . . . . . . . . . . . . . . . . . .   4
       2.1.1.  Branch-ID Sub-TLV . . . . . . . . . . . . . . . . . .   5
       2.1.2.  PPR PDE Sub-TLV . . . . . . . . . . . . . . . . . . .   6
     2.2.  OSPF TLVs . . . . . . . . . . . . . . . . . . . . . . . .   6
       2.2.1.  OSPFv2 TLVs . . . . . . . . . . . . . . . . . . . . .   6
       2.2.2.  OSPFv3 TLVs . . . . . . . . . . . . . . . . . . . . .   6
   3.  Encoding and Processing details . . . . . . . . . . . . . . .   6
     3.1.  S And D bits in PDEs  . . . . . . . . . . . . . . . . . .   7
     3.2.  Graph processing procedure example  . . . . . . . . . . .   8
   4.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
     5.1.  IS-IS IANA  . . . . . . . . . . . . . . . . . . . . . . .   9
     5.2.  OSPFv2 IANA . . . . . . . . . . . . . . . . . . . . . . .   9
     5.3.  OSPFv3 IANA . . . . . . . . . . . . . . . . . . . . . . .   9
     5.4.  IGP Parameter IANA  . . . . . . . . . . . . . . . . . . .   9
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  11
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   Preferred Path Routing (PPR) is a routing protocol mechanism
   concerned with the creation of a routing path as specified in the
   PPR-Path objects.  These can be signaled via appropriate IGPs (IS-IS,
   OSPFv2, OSPFv3) and indicate the path for a data plane identifier
   (PPR-ID).  With this, all PPR capable nodes along that path establish
   forwarding state for the PPR-ID and any packet destined to the PPR-ID
   would use that path instead of the IGP computed shortest path to the
   destination.

   PPR-Paths and relevant IGP extensions are defined in
   [I-D.chunduri-lsr-isis-preferred-path-routing] and
   [I-D.chunduri-lsr-ospf-preferred-path-routing].  In these IGP