Enterasys Networks Security Router X-PeditionTM - Manual (Page 149)

XSR User’s Guide 6-1
6
Configuring the Border Gateway Protocol
Features
The XSR supports the following the Border Gateway Protocol (BGP-4) features:
• Full mandatory BGP v4 protocol support (RFC-1771)
• Support for all BGP v4 MIB tables defined in RFC-1657 including BGP SNMP traps
• Protection of BGP Sessions: TCP MD5 Signature Option (RFC-2385)
• BGP Capabilities advertisement (RFC-2842)
• BGP Route reflection (RFC-2796)
• BGP Communities (RFC-1997)
• Route Refresh (RFC-2918)
• BGP Route Flap dampening (RFC-2439)
• AS Confederations for BGP (RFC-3065)
• BGP debug capability
Overview
BGP-4 is an Exterior Gateway Protocol (EGP) typically used to swap routing data among different
Autonomous Systems (AS). An AS is defined as a network or group of networks that run under a
common administration and with a common set of routing policies. BGP supports two types of
exchanges of routing information: exchanges between different ASs (inter-AS) and exchanges
within a single AS (intra-AS). When BGP is used between different ASs, the protocol is referred to
as External BGP (EBGP). If BGP is used to exchange routes within an AS, then the protocol is
referred to as Interior BGP (IBGP), as shown in
Figure 6-1 .