Patent ID: 7561526
Filing Date: 2009-07-14
Classification: H04L,H04W

Abstract:
1. A communications network comprising a plurality of nodes, including a source node, a destination node and a plurality of intermediate nodes, each node having a router for effecting transfer of traffic along links between the nodes, wherein a router of the source node is operable to determine from stored network topology information and measured network metrics an instantaneously best path between said node and the destination node, said instantaneously best path being entered into a routing table at a point of determination thereof, whereby to generate said instantaneously best path, and to allocate traffic to a newly determined instantaneously best path and at least one previously determined instantaneously best path in a shared manner, whereby said newly determined instantaneously best path is determined as not being the same as any of said previously determined instantaneously best paths, wherein the router of said source node is operable to provide, from said newly determined instantaneously best path and at least one said previously determined best path, a plurality of candidate stored paths, the router being further operable to determine, from current network metric values associated with each said candidate stored path, the suitability of each said candidate stored path to accept the traffic, said suitability of each stored path being determined as a weighting function value, the router being further operable to effect sharing by allocating the traffic to one at a time of said candidate stored paths in accordance with its determined suitability to carry the traffic and wherein the router of said source node is operable to allocate the traffic to a said candidate stored path on the basis of a succession of effectively random numbers within a range, the range corresponding to the sum of the weighting function values for the candidate stored paths, the router of said source node is operable to divide the range of said effectively random numbers into sections, each corresponding in size to a respective weighting function value of the candidate stored paths, and to allocate the traffic to the candidate stored path whose weighting function value corresponds to the section containing the current random number within the range.