BGP Notes – Neighbor States

Corrections appreciated.

Idle : There is no relationship, but the router sends out a TCP SYN to the neighbor to get the ball rolling.

Idle (admin) : The neighbor is admined down.

Connect : The router is waiting for the TCP connection to finish.  If the TCP connection finishes, the router sends an open and transitions to OpenSent.  If it times out, it transitions to Active.

Active : The router tries Cialis to initiate a TCP connection.  If the TCP connection finishes, the router sends an open and transitions to OpenSent.

OpenSent : The router is waiting for an open to be returned.  If one is received, the router transitions to OpenConfirm.

OpenConfirm : The router is waiting for a keepalive.  If one arrives, the router transitions to Established.

Established : The neighbor relationship is complete and updates are exchanged.

jac