An exterior gateway protocol is an IP

routing protocol A routing protocol specifies how routers communicate with each other to distribute information that enables them to select paths between nodes on a computer network. Routers perform the traffic directing functions on the Internet; data packet ...

used to exchange

routing Routing is the process of selecting a path for traffic in a Network theory, network or between or across multiple networks. Broadly, routing is performed in many types of networks, including circuit-switched networks, such as the public switched ...

information between autonomous systems. This exchange is crucial for communications across the

Internet The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...

. Notable exterior gateway protocols include Exterior Gateway Protocol (EGP), now obsolete, and Border Gateway Protocol (BGP). By contrast, an interior gateway protocol is a type of protocol used for exchanging routing information between gateways (commonly routers) within an autonomous system (for example, a system of corporate

local area network A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, campus, or building, and has its network equipment and interconnects locally managed. LANs facilitate the distribution of da ...

s). This routing information can then be used to route network-level protocols like IP.

References

Internet protocols Internet Standards Routing protocols {{Compu-network-stub