An almost optimal MAC protocol for all-optical WDM multi-rings with tunable transmitters and fixed receivers

This paper considers SRR (synchronous round robin), an almost optimal collision-free access scheme for all-optical packet networks based on WDM multi-channel ring topologies providing slotted channels for transmissions to disjoint subsets of destination nodes. Only a channel inspection capability and local status information are required at nodes in order to implement the access protocol. Since SRR is not able to enforce fairness by itself, MMR (multi MetaRing), a fairness control algorithm derived from those adopted in the MetaRing high-speed metropolitan area network, is superimposed to SRR. Our analysis proves that the considered access scheme, in spite of its simplicity, allows an almost optimal exploitation of the available resources while guaranteeing a fair access to all nodes.