A system for routing packets in a network environment having a connection-oriented subnetwork, a plurality of routers coupled to said connection-oriented subnetwork, and a plurality of established virtual circuits. A packet is received by a router for forwarding toward a packet destination....http://www.google.com.tw/patents/US5699347?utm_source=gb-gplus-share專利 US5699347 - Method and apparatus for routing packets in networks having connection-oriented subnetworks 
