Proposal and Implementation of an Autonomous Distributed Control for Elimination of Incomplete Lightpaths in Optical Packet and Circuit Integrated Networks

摘要

We are developing an optical packet and circuit integrated network. When a process of lightpath establishment or release fails due to discarding of signaling packets on the network, some nodes are burdened with undesired optical path-connections remaining in themselves. It is possible that our conventional system requires a long time to eliminate such an incomplete lightpath. In this paper, we propose and implement a novel autonomous distributed control for elimination of incomplete lightpaths. In our proposed system, lightpath refreshing messages are generated and transferred by means of the same procedure as signaling. Thereby, when a lightpath establishment or release fails, any nodes can recognize the failures at about the same time because the sender does not transmit lightpath refreshing messages. As a result, the time required to eliminate incomplete lightpaths can be reduced, and furthermore the proposed system is sufficiently robust. Besides, our proposed signaling function is properly interlocked with a dynamic resource-adjustment control, and thus the status of usage of lightpaths in the network can automatically recover.