Scalable BGP FRR Protection against Edge Node Failure
draft-bashandy-bgp-edge-node-frr-01

The information below is for an old version of the document
Document Type Active Internet-Draft (individual)
Last updated 2011-10-28 (latest revision 2011-07-10)
Stream (None)
Intended RFC status (None)
Formats plain text pdf html bibtex
Stream Stream state (No stream defined)
Consensus Boilerplate Unknown
RFC Editor Note (None)
IESG IESG state I-D Exists
Telechat date
Responsible AD (None)
Send notices to (None)
Network Working Group                                       A. Bashandy
Internet Draft                                            Cisco Systems
Intended status: Standards Track                       October 26, 2011
Expires: April 2012

          Scalable BGP FRR Protection against Edge Node Failure
                 draft-bashandy-bgp-edge-node-frr-01.txt

Abstract

Consider a BGP free core scenario. Suppose the edge BGP speakers PE1,
PE2,..., PEn know about a prefix P/p via the external routers CE1,
CE2,..., CEm.  If the edge router PEi crashes or becomes totally
disconnected from the core, it desirable for a penultimate hop route
"P" carrying traffic to the failed edge router PEi to immediately
restore traffic by re-tunneling packets originally tunneled to PEi
and destined to the prefix P/p to one of the other edge routers that
advertised P/p, say PEj, until BGP re-converges. In doing so, it is
highly desirable to keep the core BGP-free while not imposing
restrictions on external connectivity. Thus (1) a core router should
not be required to learn any BGP prefix, (2) the size of the
forwarding and routing tables in the core routers should be
independent of the number of BGP prefixes,(3) there should be no
special router (or group of routers) that handles restoring traffic,
and (4) there should be no restrictions on what edge routers
advertise what prefixes. For labeled prefixes, (5) the penultimate
hop router must swap the label advertised by the failed edge router
PEi for the prefix P/p with the label advertised for the same prefix
by the edge router PEj before re-tunneling the packet to PEj

Status of this Memo

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

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008. The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s)
   controlling the copyright in such materials, this document may not
   be modified outside the IETF Standards Process, and derivative
   works of it may not be created outside the IETF Standards Process,
   except to format it for publication as an RFC or to translate it
   into languages other than English.

Bashandy                Expires April 26, 2012                 [Page 1]
Internet-Draft        BGP FRR using Repair Label           October 2011

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on April 26, 2012.

Copyright Notice

   Copyright (c) 2011 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. Problem definition........................................4
      1.2. Conventions used in this document.........................5
      1.3. Terminology...............................................5
   2. Control Plane Operation........................................6
      2.1. Control plane Operation for unlabeled prefixes............6
         2.1.1. Step 1: Calculation of the Repair PE.................7
         2.1.2. Step 2: Assigning and Advertising the BGP Next-hop...7
         2.1.3. Step 3: Informing Core Routers about the Repair PE...7
         2.1.4. Step 4: How a P router (a core router) Programs its
         Forwarding Plane............................................8

Bashandy                Expires April 26, 2012                 [Page 2]
Show full document text