(1) (
Exterior
Gateway
Protocol) A broad category of routing protocols that are designed to span different autonomous systems. Contrast with
IGP.
(2) (
Exterior
Gateway
Protocol) The original exterior gateway routing protocol (see above), which was widely used in the U.S. Data Defense Network (DDN) and National Science Foundation Network (NSFNet). EGP was a distance vector protocol that used polling to retrieve routing information. EGP was superseded by BGP. See
BGP and
routing protocol.