Autonomous System An AS is a group of Open Shortest Path First (OSPF) routers that exchange information, typically under the control of one company An AS can include a large number of networks, all of which share the same AS number All information exchanged within the AS is interior Exterior protocols, such as Exterior Gateway Protocol (EGP), exchange routing information between one AS and another Using an EGP, the MAX TNT imports external routes into its OSPF database and flags them as ASE (Autonomous System External) See also ASE, EGP, external route, OSPF, router