Browse Prior Art Database

Restart Signaling for IS-IS (RFC5306)

IP.com Disclosure Number: IPCOM000175194D
Original Publication Date: 2008-Oct-01
Included in the Prior Art Database: 2008-Oct-05
Document File: 23 page(s) / 51K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

M. Shand: AUTHOR [+2]

Abstract

This document describes a mechanism for a restarting router to signal to its neighbors that it is restarting, allowing them to reestablish their adjacencies without cycling through the down state, while still correctly initiating database synchronization.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 5% of the total text.

Network Working Group                                           M. Shand Request for Comments: 5306                                   L. Ginsberg Obsoletes: 3847                                            Cisco Systems Category: Standards Track                                   October 2008

                       Restart Signaling for IS-IS

Status of This Memo

   This document specifies an Internet standards track protocol for the    Internet community, and requests discussion and suggestions for    improvements.  Please refer to the current edition of the "Internet    Official Protocol Standards" (STD 1) for the standardization state    and status of this protocol.  Distribution of this memo is unlimited.

Abstract

   This document describes a mechanism for a restarting router to signal    to its neighbors that it is restarting, allowing them to reestablish    their adjacencies without cycling through the down state, while still    correctly initiating database synchronization.

   This document additionally describes a mechanism for a restarting    router to determine when it has achieved Link State Protocol Data    Unit (LSP) database synchronization with its neighbors and a    mechanism to optimize LSP database synchronization, while minimizing    transient routing disruption when a router starts.  This document    obsoletes RFC 3847.

 Shand & Ginsberg            Standards Track                     [Page 1]
 RFC 5306              Restart Signaling for IS-IS           October 2008

 Table of Contents

   1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .  3

   2.  Conventions Used in This Document  . . . . . . . . . . . . . .  4

   3.  Approach . . . . . . . . . . . . . . . . . . . . . . . . . . .  4

     3.1.  Timers . . . . . . . . . . . . . . . . . . . . . . . . . .  4

     3.2.  Restart TLV  . . . . . . . . . . . . . . . . . . . . . . .  5

       3.2.1.  Use of RR and RA Bits  . . . . . . . . . . . . . . . .  6

       3.2.2.  Use of the SA Bit  . . . . . . . . . . . . . . . . . .  8

     3.3.  Adjacency (Re)Acquisition  . . . . . . . . . . . . . . . .  8

       3.3.1.  Adjacency Reacquisition during Restart . . . . . . . .  9

       3.3.2.  Adjacency Acquisition during Start . . . . . . . . . . 11

       3.3.3.  Multiple Levels  . . . . . . . . . . . . . . . . . . . 12

     3.4.  Database Synchronization . . . . . . . . . . . . . . . . . 13

       3.4.1.  LSP Generation and Flooding and SPF Computation  . . . 14

         3.4.1.1.  Restarting . . . . . . . . . . . . . . . . . . . . 14

         3.4.1.2. ...