Exact and Approximate Analytical Modeling of an FLBM-Based All-Optical Packet Switch

This paper develops both exact and approximate models for the analysis of an all-optical packet switch based on a fiber-loop buffer memory (FLBM). The switch structure and operation is based on the fully shared buffer architecture of the Research and Development in Advanced Communications in Europe—ATM Optical Switching (RACE-ATMOS) project [1], which uses individual wavelengths to store fixed-length packets in the fiber-loop buffer. An exact model of the switch has been developed [2], which can be used to determine the blocking performance of the switch and obtain both its throughput and packet loss characteristics. It has been used to study the switch performance under different loading conditions and for different values of the key design parameters of the switch. This model is difficult to use for studying large switches of this kind because of computational complexities. To tackle this problem, an approximate queuing model has also been presented, which may be used to study the performance of large switches of this kind. The results obtained by the two methods are compared to confirm that the approximate model works well under typical loading conditions of the switch.