BGP (Border Gateway Protocol) is a routing protocol used to exchange routing information between different networks on the internet. BGP ensures network availability by:
1. Redundancy: BGP allows multiple paths to a destination network, increasing network availability by providing alternative routes when one fails.
1. Best path selection: BGP selects the best path to a destination network based on several criteria, such as the shortest path or the least number of AS (Autonomous System) hops.
1. Route convergence: BGP enables quick convergence of network routes, which means that any network changes are quickly propagated to other routers in the network, ensuring that the network is always available.
1. Peer agreements: BGP requires that routers establish agreements with their peers before exchanging routing information. These agreements ensure that routes are exchanged only when both routers have agreed to do so and that they are in sync with each other.
1. Security: BGP supports various security measures like access control lists, AS path filtering, and community strings to prevent unauthorized access and attacks on the network. These security measures enhance network availability by protecting the network from malicious attacks and intrusions.
