EGP or Interdomain Routing Protocols are #Routing Protocol used between the Autonomous System (AS)# (interdomain). Most of them are of type Path-Vector Routing Protocol#.
Examples of such protocol are:
BGPv4 is a widely adopted #Exterior Gateway Protocols (EGP) by Internet Service Provider (ISP) which is available for both IPv4 Address and IPv6 Address)
AS is a #logical network segment that contains several Network Devices# especially Routers# under a common administration sharing a common routing strategy. An AS is typically identified using 16-bit autonomous system number (ASN) given by the American Registry of Internet Numbers (ARIN), an Internet Service Provider (ISP) or a network administrator. It is a basic unit in Routing inside AS involves #IGP whereas routing outside AS involves #EGP.