User Manual

Enterasys X-Pedition User Reference Manual 205
BGP Configuration Examples
parameters). Upon successful completion of the BGP Open negotiations, BGP Update messages
containing the BGP routing table can be sent between peers.
BGP does not require a periodic refresh of the entire BGP routing table between peers. Only
incremental routing changes are exchanged. Therefore, each BGP speaker is required to retain the
entire BGP routing table of their peer for the duration of the peer’s connection.
BGP “keepalive” messages are sent between peers periodically to ensure that the peers stay
connected. If one of the routers encounters a fatal error condition, a BGP notification message is
sent to its BGP peer, and the TCP connection is closed.
Figure 12 illustrates a sample BGP peering session.
Figure 12. Sample BGP Peering Session
Physical Link
Legend:
Peering Relationship
AS-2
X-Pedi
10.0.0.2/16
10.0.0.1/16
X-Pedi
AS-1
1.1
1.1