Routing over large clouds

摘要: The present invention discloses an efficient architecture for routing in a very large autonomous system where many of the layer 3 routers are attached to common connection-oriented 2 subnetwork, such as ATM network. In preferred embodiment invention, permanent topology coupled subnetwork is connected by virtual circuits. can further take advantage both intra-area and inter-area shortcuts through network improve performance. pre-calculate using information from link state packets broadcast other store given destination forwarding table, along with corresponding entries next hop topology. allows continue operate correctly if resource limitations preclude setup additional shortcuts.