Avaya Configuring IP Exterior Gateway Protocols (BGP and EGP) Instrukcja Użytkownika Pobierz pdf (Strona 25)

Exterior Gateway Protocols (BGP/EGP)

308628-14.00 Rev 00

1-5

Nortel Networks supports BGP-3 and BGP-4:

• BGP-3 assumes that each advertised network is a natural class network (A, B,

or C), based on its high-order bits. BGP-3 cannot advertise subnets or

supernets.

• BGP-4 has no concept of address classes. Each network listed in the network

layer reachability information (NLRI) portion of an update message contains

a prefix length field, which describes the length of the mask associated with

the network. This allows for both supernet and subnet advertisement. The

supernet advertisement is what makes classless interdomain routing (CIDR)

possible.

In addition, BGP-4 supports BGP confederations and TCP MD5 message

authentication.

This chapter covers the following topics:

Peer-to-Peer Sessions

A BGP router employs a BGP speaker, which is an entity within the router that

transmits and receives BGP messages and acts upon them. A BGP speaker forms

a neighbor relationship with another BGP speaker by establishing a peer-to-peer

session. See Chapter 6, “Establishing a Peer-to-Peer Session

.”

Topic Page

Peer-to-Peer Sessions

1-5

Stub and Multihomed Autonomous Systems 1-6

Interior BGP Routing 1-6

IBGP Route Reflector 1-7

Equal-Cost Multipath 1-8

BGP Updates 1-8

BGP/OSPF Interaction 1-10

BGP-4 Confederations 1-10

BGP-4 TCP MD5 Message Authentication 1-11

BGP Implementation Notes 1-11

1 2 ... 20 21 22 23 24 25 26 27 28 29 30 ... 307 308

Brak uwag

Avaya Configuring IP Exterior Gateway Protocols (BGP and EGP) Instrukcja Użytkownika Strona 25