Browse Prior Art Database

Point-to-Point Operation over LAN in Link State Routing Protocols (RFC5309)

IP.com Disclosure Number: IPCOM000175197D
Original Publication Date: 2008-Oct-01
Included in the Prior Art Database: 2008-Oct-05
Document File: 11 page(s) / 21K

Publishing Venue

Internet Society Requests For Comment (RFCs)

Related People

N. Shen: AUTHOR [+4]

Abstract

The two predominant circuit types used by link state routing protocols are point-to-point and broadcast. It is important to identify the correct circuit type when forming adjacencies, flooding link state database packets, and representing the circuit topologically. This document describes a simple mechanism to treat the broadcast network as a point-to-point connection from the standpoint of IP routing.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 13% of the total text.

Network Working Group                                       N. Shen, Ed. Request for Comments: 5309                                 Cisco Systems Category: Informational                                    A. Zinin, Ed.                                                           Alcatel-Lucent                                                             October 2008

                    Point-to-Point Operation over LAN                     in Link State Routing Protocols

Status of This Memo

   This memo provides information for the Internet community.  It does    not specify an Internet standard of any kind.  Distribution of this    memo is unlimited.

Abstract

   The two predominant circuit types used by link state routing    protocols are point-to-point and broadcast.  It is important to    identify the correct circuit type when forming adjacencies, flooding    link state database packets, and representing the circuit    topologically.  This document describes a simple mechanism to treat    the broadcast network as a point-to-point connection from the    standpoint of IP routing.

1.  Introduction

   Point-to-point and broadcast are the two predominant circuit types    used by link state routing protocols such as IS-IS [ISO10589]    [RFC1195] and OSPF [RFC2328] [RFC5340].  They are treated differently    with respect to establishing neighbor adjacencies, flooding link    state information, representing the topology, and calculating the    Shortest Path First (SPF) and protocol packets.  The most important    differences are that broadcast circuits utilize the concept of a    designated router and are represented topologically as virtual nodes    in the network topology graph.

   Compared with broadcast circuits, point-to-point circuits afford more    straightforward IGP operation.  There is no designated router    involved, and there is no representation of the pseudonode or network    Link State Advertisement (LSA) in the link state database.  For IS-    IS, there also is no periodic database synchronization.  Conversely,    if there are more than two routers on the LAN media, the traditional    view of the broadcast circuit will reduce the routing information in    the network.

Shen & Zinin                 Informational                      [Page 1]
 RFC 5309                      P2P over LAN                  October 2008

    When there are only two routers on the LAN, it makes more sense to    treat the connection between the two routers as a point-to-point    circuit. ...