a router connected to more than one autonomous system (AS), and which exchanges routing information with routers in other ASs

autonomous system boundary router. A router that exchanges routing information with routers that belong to other autonomous systems. The AS boundary router then advertises external routes throughout the autonomous system. AS boundary routers can be internal or area border routers, and migh or might not be connected to the backbone.

Autonomous system boundary router. In OSPF, a router that exchanges routing information with routers in other ASs.