Cisco ASR 9000 Series

CHAPTER 2
Implementing BGP
Border Gateway Protocol (BGP) is an Exterior Gateway Protocol (EGP) that allows you to create loop-free
interdomain routing between autonomous systems. An autonomous system is a set of routers under a single
technical administration. Routers in an autonomous system can use multiple Interior Gateway Protocols
(IGPs) to exchange routing information inside the autonomous system and an EGP to route packets outside
the autonomous system.
This module provides the conceptual and configuration information for BGP on Cisco IOS XR software.
For more information about BGP and complete descriptions of the BGP commands listed in this module,
see Related Documents, on page 168 section of this module. To locate documentation for other commands
that might appear while performing a configuration task, search online in the Cisco ASR 9000 Series
Router software master command index.
Note
Feature History for Implementing BGP
ModificationRelease
This feature was introduced.Release 3.7.2
The following features were supported:
•
BGP Prefix Independent Convergence Unipath Primary
Backup
•
BGP Local Label Retention
•
Asplain notation for 4-byte Autonomous System Number
•
BGP Nonstop Routing
•
Command Line Interface (CLI) consistency for BGP
commands
•
L2VPN Address Family Configuration Mode
Release 3.9.0
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
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