Provisioning of connection through a sonet/sdh network

Abstract

A method of provisioning a connection across a SONET/SDU network formed from multiple sub-networks comprises: determining a model of the entire network, the model indicating the connections between all sub-networks, and representing each sub-network as a single unit; calculating a route between the sub-networks containing the first and second nodes using the model; passing the signals along the determined route, and determining the route between nodes within each sub-network locally within the respective sub-network. This method enables a simplified model of the network to be stored in each node of the network, so that a route calculation can take place at the sending node. The specific route through the network is determined as the signal passes through the network, as the specific path through individual sub-networks is determined locally. Thus, each node only needs to be capable of calculating a general route using the simplified model of the whole network and also capable of calculating a specific route through the sub-network of the node itself.