SR3: A Bandwidth-Reservation MAC Protocol for Multimedia Applications over All-Optical WDM Multi-Rings

The paper describes SR3 (Synchronous Round Robin with Reservations), a collision-free medium access control protocol for all-optical slotted packet networks based on WDM multi-channel ring topologies where nodes are equipped with one fixed-wavelength receiver and one wavelength-tunable transmitter. SR3 is derived from the S R R and MMR protocols previously proposed b y the same authors for the same class of all-optical networks. S R R and MMR already achieve an eficient exploitation of the available bandwidth, while guaranteeing a throughput-fair access t o each node. SR3, in addition, allows nodes to reserve slots, thereby achieving a stronger control on access delays; it is thus well suited to meet tight delay requirements, as it is the case for multimedia applications. Simulation results show that SR3 provides very good performance to guaranteed quality trafic, but also brings significant performance improvements for besteffort trafic.