An Open message has been both sent to and received from the other

router. Next step is to receive a BGP Keepalive message (to confirm that all

neighbor-related parameters match) or a BGP Notification message (to learn that

there is some mismatch in neighbor parameters).

All neighbor parameters matched, the neighbor relationship has been

established and the peers can now exchange Update messages

BGP will try another TCP three-way handshake to establish a connection

with the remote BGP neighbor. If it is successful, it will move to the OpenSent

state.

The TCP connection exists, and a BGP Open message has been sent to the

peer, but the matching Open message has not yet been received from the other

router.

The BGP process is either administratively down or waiting for the the

next retry attempt.

The BGP process is waiting for the TCP connection to be completed. If it

is successful, it will continue to the OpenSent state. In case it fails, it

will continue to the Active state.