Hybrid centralized/distributed precomputation of network signal paths

Abstract

Precomputation techniques for determining primary and/or restoration paths in an optical or electrical network. A hybrid centralized/distributed approach is provided in which certain information used in distributed precomputation is downloaded from a central controller of the network. The downloaded information is used as an input to a distributed precomputation algorithm implemented by the network nodes in order to provide improved performance. The central controller makes use of its knowledge of global network topology in computing the information to be downloaded to the nodes. The downloaded information generally represents network information which changes with less frequency than other network information processed by the nodes as part of the distributed precomputation algorithm. The information downloaded from the central controller may include, for example, network connectivity information, capacities for at least a subset of the links in the network, a subset of all possible routes between a source node and a destination node in the network arranged in an appropriate initial search order, a link contention index for each of the links in the network, and indices assigned to one or more of the nodes and links of the network, wherein the indices are used to determine an order of processing operations involving the one or more nodes and links of the network.