Path segment protecting p-cycles

摘要

This disclosure introduces a significant extension to the method of p-cycles for network protection. The main advance is the generalization of the p-cycle concept to protect multi-span segments of contiguous working flow, not only spans that lie on the cycle or directly straddle the p-cycle. This effectively extends the p-cycle technique to include path protection, or protection of any flow segment along a path, as well as the original span protecting use of p-cycles. It also gives an inherent means of transit flow protection against node loss. We present a capacity optimization model for the new scheme and compare it to prior p-cycle designs and other types of efficient mesh-survivable networks. Results show that path-segment-protecting p-cycles (“flow p-cycles” for short) have capacity efficiency near that of a path-restorable network without stub release. An immediate practical impact of the work is to suggest the of use flow p-cycles to protect transparent optical express flows through a regional network.

主权项

1. A telecommunications network, comprising:
plural nodes connected by plural spans and arranged to form a mesh network; at least one pre-configured cycle of spare capacity being established in the mesh network, the pre-configured cycle including plural nodes of the mesh network and being pre-configured prior to a span or node failure; and the plural nodes of the pre-configured cycle being configured to protect at least one path segment, where the path segment includes at least a first intersecting node and a second intersecting node within the pre-configured cycle and at least one intermediate node in a path that includes the first intersecting node and second intersecting node and straddles the pre-configured cycle, the intermediate node not being a part of the pre-configured cycle, and the pre-configured cycle being configured to protect the path segment by the first intersecting node and the second intersecting node being pre-configured to reroute a working signal from the path segment to the pre-configured cycle in response to a signal indicating the failure of a span of the path segment, the span of the path segment being non-adjacent to at least one of the first intersecting node and the second intersecting node.