1-Persistent Collision-Free CSMA Protocols for Opportunistic Optical Hyperchannels

Recently, a new WDM optical network infrastructure named SMART [1], which is capable of dynamically setting up, modifying, and tearing down optical connections, was proposed. The performance of SMART is determined by the performance of its hyperchannels, which are essentially optical buses or light-trails. Previously proposed MAC protocols for unidirectional optical buses can be used as distributed medium access control protocols for hyperchannels. However, these protocols require optical detection and they are either unfair, or not work-conserving. In this paper, we propose a class of workconserving, collision-free, detection-free, and fair MAC protocols for opportunistic hyperchannels which are tailored hyperchannels for SMART. We compare our proposed MAC protocols with known pi-persistent CSMA protocols and priority-based CSMA protocol by simulations. We show that the performances of our proposed protocols are much better than that of pi-persistent CSMA and that of priority-based CSMA protocol in terms of throughput and fairness. keywords Optical network, WDM, MAC, CSMA, SMART network, light-trail, opportunistic hyperchannel