Exterior Gateway Protocol (EGP) is a type of routing protocol used to exchange routing information between different autonomous systems (ASes) in a network. Unlike Interior Gateway Protocols (IGPs), which focus on routing within a single AS, EGP is designed to facilitate routing between separate administrative domains.
The primary purpose of EGP is to enable routers in different autonomous systems to share information about network reachability and paths for data packet forwarding. This allows routers to determine the best routes for sending data packets across the internet, ensuring that data can traverse multiple networks to reach its final destination.
The most well-known and widely used Exterior Gateway Protocol is BGP (Border Gateway Protocol), which is extensively used in the global internet routing system. BGP helps determine the most efficient paths for routing data packets between autonomous systems based on various attributes and policies.
EGP protocols are essential for maintaining the stability and efficient operation of the internet. They enable the global network to function by ensuring that data can be properly routed across different autonomous systems, allowing users and devices to communicate seamlessly across diverse networks.