Abstract: A system for managing virtual circuits and determining proper routing of packets in a network environment. The network includes a connection-oriented subnetwork and an arrangement of routers coupled to the connection-oriented subnetwork. The system determines paths to each exit router by considering all possible paths through the connection-oriented subnetwork. The system also determines paths to each exit router by considering existing virutal circuits through the connection-oriented subnetwork. Finally, the system determines and establishes a most beneficial new virtual circuit for the network. Additionally, the rate at which new virtual circuits are established may be regulated by the system.

Abstract: 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. A best existing virtual circuit across said connection-oriented subnetwork is identified from said plurality of established virtual circuits. The best existing virtual circuit is analyzed to determine whether it is both feasible and efficient for forwarding the packet toward the packet destination. If the best existing virtual circuit is both feasible and efficient, then the packet is forwarded using the best existing virtual circuit. If the best existing virtual circuit is either not feasible or inefficient, then a new virtual circuit is established to an optimal next hop router and the packet is forwarded using the new virtual circuit.

Abstract: 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. A best existing virtual circuit across said connection-oriented subnetwork is identified from said plurality of established virtual circuits. The best existing virtual circuit is analyzed to determine whether it is both feasible and efficient for forwarding the packet toward the packet destination. If the best existing virtual circuit is both feasible and efficient, then the packet is forwarded using the best existing virtual circuit. If the best existing virtual circuit is either not feasible or inefficient, then a new virtual circuit is established to an optimal next hop router and the packet is forwarded using the new virtual circuit.

Abstract: An internetwork routing protocol which supports virtual networks. Routing tables are maintained in routers or gateways which identify whether or not a destination is directly reachable by the router listed in the routing information entry, or whether it is merely part of a virtual network served by the listed destination routers. For directly reachable connections, datagrams may be directly delivered to any router claiming such status with respect to the network with assurance of likely delivery to the destination. Routers in communication with a virtual network must first be queried for the identity of a particular destination router address before packets are delivered to eliminate the need of packet forwarding.

Abstract: A method for connecting a network so that TCP/IP and OSI 8473 packets may be routed in the same domain. The independence of the addresses is maintained: one device in the network may be assigned only a TCP/IP address, and another device may be assigned only a ISO 8473 address. Furthermore, all of the routers share link state information by using a common link state packet format (such as the ISO 10589 format); thus routes through the network may be computed without regard for the protocols supported by the routers along the route. Where necessary, packets are encapsulated and forwarded through routers which are not capable in the protocol of the packet. In some disclosed embodiments, all of the routers in a given area support a given protocol (or, in fact, have identical capabilities, in which case encapsulation is not required). In these embodiments, the encapsulation is performed by suitable modifications to each router's packet forwarding procedures.

Abstract: A method for connecting a network so that TCP/IP and OSI 8473 packets may be routed in the same domain. The independence of the addresses is maintained: one device in the network may be assigned only a TCP/IP address, and another device may be assigned only a ISO 8473 address. Furthermore, all of the routers share link state information by using a common link state packet format (such as the ISO 10589 format); thus routes through the network may be computed without regard for the protocols supported by the routers along the route. Where necessary, packets are encapsulated and forwarded through routers which are not capable in the protocol of the packet. In some disclosed embodiments, all of the routers in a given area support a given protocol (or, in fact, have identical capabilities, in which case encapsulation is not required). In these embodiments, the encapsulation is performed by suitable modifications to each router's packet forwarding procedures.