AN EFFICIENT TRANSMISSION SCHEDULING ALGORITHM FOR A WAVELENGTH-REUSABLE LOCAL LIGHTWAVE NETWORK

Although single-hop star networks based on wavelength division multipl exing (WDM) are attractive owing to their all-optical communication fe atures, the throughput of such lightwave networks is limited due to th e small number of available wavelengths. In this paper, a wavelength-r eusable local lightwave network that consists of two interconnected WD M star networks is proposed. Based on this architecture, the lower bou nds for the problems of minimizing the switching duration and the numb er of switching modes are derived. A transmission scheduling algorithm for this architecture to efficiently reuse the wavelengths is also pr oposed. The analytical result shows that the proposed scheduling algor ithm always produces solutions close to the lower bounds. Simulation r esults show that given the same number of users and available waveleng ths, the solutions (in terms of the average switching duration and the average number of switching matrices) obtained by the proposed schedu ling algorithm on the interconnected WDM networks are better than the optimal solution on a single-star WDM network. In most cases, the perf ormance improvement achieves 20 to 45%.