Interior and Exterior Routing Protocols

Interior and Exterior Gateway Protocols (IGP and EGP) are two different types of routing protocols used to exchange routing information between routers in a network.

Interior Gateway Protocols (IGP) are used to share routing information within an autonomous system (AS) or a network domain. IGP protocols are used to establish the best path between networks and to distribute routing information within a network. Examples of IGP routing protocols include:

Routing Information Protocol (RIP)

Open Shortest Path First (OSPF)

Intermediate System to Intermediate System (IS-IS)

Enhanced Interior Gateway Routing Protocol (EIGRP)

Exterior Gateway Protocols (EGP) are used to exchange routing information between different autonomous systems. EGP protocols are used to exchange information between networks that are not directly connected to each other. Examples of EGP protocols include: Border Gateway Protocol (BGP)