Performance evaluation of multipriority reservation protocols for single-hop WDM networks

Abstract

We propose two multipriority reservation protocols for wavelength division multiplexing (WDM) networks. The network architecture is a single-hop with control channel-based passive star topology. Each station is equipped with two pairs of laser and filter. One pair of laser and filter is always tuned to wavelength lambda(0) for control and the other pair of laser and filter can be tuned to any of data wavelengths, lambda(1), lambda(2), ..., lambda(N). According to the access methods of the control channel, one protocol is called slotted ALOHA-based protocol and the other protocol is called TDM-based protocol. The two protocols have the following properties. First, each of them has its own priority control scheme which easily accommodates multipriority traffics. Second, they can be employed in the network with limited channels, i.e. the number of stations in the system is not restricted by the number of data channels. Third, they are conflict-free protocols. By using a reservation scheme and a distributed arbitration algorithm, channel collision and destination conflict can be avoided. For the performance point of view, the TDM-based protocol gives an optimal solution for the priority control. However it is less scalable than the slotted ALOHA-based protocol. The slotted ALOHA-based protocol also performs good priority control even though it is not an optimal solution. We analyze their performances using a discrete time Markov model and verify the results by simulation.