Routing protocols are broadly classified as Interior Gateway Protocols (IGP) or Exterior Gateway Protocols (EGP). IGPs are used to exchange routing information within internetworks that fall under a single administrative domain (also called Autonomous Systems). EGPs on the other hand are used to exchange routing information between different autonomous systems. Common examples of IGPs are Routing Information Protocol (RIP), Enhanced Interior Gateway Routing Protocol (EIGRP) and Open Shortest Path First (OSPF). These are covered in detail in the next chapter. On the other hand, Border Gateway Protocol (BGP) is an example of EGP. It is the protocol used for routing information exchange on Internet. It is beyond the scope of CCNA, hence we will not cover it in this book.