BGP Explained in detail || BGP Overview, Message Types, States || CCNA & CCNP

This video contains the discussion about the BGP Routing protocol. BGP : Border Gateway Protocol BGP is a Exterior Gateway Protocol that is used to share the route information between different Autonomous sytem. Open standard EGP Designed for huge inter-network like Internet. Updates are incremental and trigger Path Vector Protocol It is application layer protocol uses port 179 TCP It sends update to the manually defined neighbor as unicast Metrics - Attributes (Many) AD - 20External and 200 IBGP Loop prevention mechanism Slowest routing protocol in the world Message Types ================ Open used to initiate a BGP session between 2 routers. includes : BGP version Sender AS number Hold Time (Cisco default 180 seconds) BGP identifier optional parameter If want to reject the BGP open, then Notification message will be sent. Keepalive I am still alive, lets keep this BGP session open. it will be sent one-third the "hold time", cisco default every 60 seconds. update If any new route added and existing route deleted. Path Attributes notification Terminate or rejects a BGP connection. Can include error message (" BGP version not supported") ========= BGP States: =============== Idle BGP process just started up or BGP error just occurred Connect Initiated TCP socket to neighbor Active Repeatedly attempting TCP handshake to connect to neighbor Open sent TCP socket established, sent open message Open Confirm Received reply open back Established We have received a keepalive or update and are exchanging the data