OpenSent state

OpenSent state In the OpenSent state, the BGP speaker is waiting to receive an OPEN message
from the remote BGP speaker. Once the BGP speaker receives the OPEN message, all of the fields
are checked. If an error is detected by the BGP speaker, it sends a NOTIFICATION message to
the remote BGP speaker and terminates the TCP, and the state of the BGP speaker transitions
to Idle. If no errors are found with the OPEN message, the BGP speaker sends a KEEPALIVE message
to the remote BGP speaker, sets the keepalive timer, and sets the hold timer to the negotiated
value. The BGP speakers then negotiate the holdtime. A negotiated value of 0 means that the keepalive
timer and the hold timer will never be reset. After the holdtime has been negotiated, the BGP
speaker determines whether the connection will be iBGP or eBGP, because this will affect the
UPDATE processing discussed shortly. If the two BGP speakers are in the same autonomous system,
the BGP type will be iBGP. If they are in different autonomous systems, the BGP type will be
eBGP. Once the type of BGP has been determined, the state transitions to OpenConfirm. During
this state, it is possible that the BGP speaker may receive a TCP disconnect message. If this should
occur, the BGP speaker transitions to the Active state. If any other types of events cause an error,
the BGP speaker closes the TCP connection and transitions its state to Idle. All BGP start events
are ignored in the OpenSent state.