초록 ▼

Method and apparatus providing connection-oriented services for packet switched data communications networks. Directory services include distributed discovery of MAC addresses and protocol alias addresses. Topology services include a link state topology exchange among switches, which provides each s

Method and apparatus providing connection-oriented services for packet switched data communications networks. Directory services include distributed discovery of MAC addresses and protocol alias addresses. Topology services include a link state topology exchange among switches, which provides each switch with a complete topology graph of the network. This enables an access switch receiving a data packet to determine a complete path from a source end system to a destination end system. Another service includes resolution of broadcast frames to unicast frames, in order to reduce the amount of broadcast traffic. Policy restrictions may be applied prior to connection setup. Path determination services enable multiple paths from a source to a destination. Connection management includes source routed mapping of connections on the desired path. A distributed call rerouting service is provided wherein if a link on an active path fails, each switch receives a topology change notification and unmaps any connection involving the failed link. A broadcast/unknown service provides restricted flooding of nonresolvable packets. Furthermore, connection-oriented switching is provided based on the source and destination MAC addresses as a connection identifier. Still further, resolution of networks outside the switch domain is enabled by access switches listening for network and server route advertisements and maintaining best routes to said networks and servers. The best route metrics may be combined with best path metrics to determine a path from a first access switch to an egress switch connected to the external network.

대표청구항 ▼

[ We claim:] [1.] A method of forwarding data packets in a switched communications network, the network including a plurality of end systems and switches connected by links, the switches having access ports connected to end systems and network ports connected to other switches, and each end system h

[ We claim:] [1.] A method of forwarding data packets in a switched communications network, the network including a plurality of end systems and switches connected by links, the switches having access ports connected to end systems and network ports connected to other switches, and each end system having a unique physical address, the method comprising the steps of:each one of the switches maintaining a directory of local mappings for access ports or end systems attached to the access ports of the one switch and remote mappings of end systems or access ports attached to other switches;when a first packet is received on an access port of a first switch, the first switch accessing its directory to find a mapping according to a destination address in the first packet;when a mapping is not found at the first switch in the director, forwarding a resolve message from the first switch to other switches, the forwarded resolve message being a request for a resolution from another switch according to the destination address in the first packet; andthe first switch waiting for a response to its forwarded resolve message prior to forwarding the first packet.