Impact of propagation delay on media access protocol performance for star-coupled WDM local area networks

The authors evaluate the impact of propagation delay on the performance of media access protocols for star-coupled wavelength-division multiplexed (WDM) photonic local area networks. The relative impact on preallocation and reservation based protocols is evaluated. I-SA and I-TDMA are designed for a network where channels are preallocated to the nodes for reception where each node has a home channel it uses for all data packet receptions. TDMA-C is control channel based, with one WDM channel allocated to reserve access for data packet transmission on the remaining data channels. Control channel access arbitration is achieved through time-division multiplexing, enabling all active nodes the opportunity to transmit once every control cycle. The performance of the protocols is evaluated through discrete-event simulation in terms of network throughput, packet delay, and data channel utilization