Method and system for routing messages in a multi-node data communication network

摘要

The invention relates to a method and a system for routing messages or frames through network nodes connected to each other by network links and connected to a plurality of terminals by different input/output ports also called network attachment cards (NAC) in a multi-node communication network. In such a configuration, each terminal equipment stores a network table. The network table is updated in the terminal itself by a network manager which may by the way limit the access of the terminal to some terminals of the network. To route an incoming message or frame from a source terminal (T1) to the destination terminal (T7), a routing algorithm is implemented in each NAC. Each NAC has a different and unique integer address in the node, each node has a different and unique prime number address greater than the number of NACs in the node. Each terminal connected to a node sends frames with a routing identifier (RI). The different RIs are located in the network table. When an input NAC receives a frame, the routing algorithm computes the address of the output NAC given by the remainder of the division of the RI by the node address, then this output NAC sends the frames onto its network link. This process is performed in each node until the destination terminal is reached. The RI is kept unchanged during the frame transmission. A timer is also used to test if the frame is received because a network link may be down. In such case, an alternate RI is used to take an alternate route.