A comparison study on the number of wavelength converters needed in synchronous and asynchronous all-optical switching architectures

The objective of this study is to investigate the performances of packet-switching architectures working in a synchronous and asynchronous way; in such architectures, the packet contention is resolved in the wavelength domain and the used wavelength converters are shared. We investigate on the saving of the number of converters that the sharing technique allows to obtain in the synchronous and asynchronous architectures and compare the obtained results. These ones show that when a packet loss probability is fixed, in the synchronous case a greater number of converters is saved. In some cases, the gain is 40% more than the asynchronous case. Furthermore, in the asynchronous case, a more expensive switching matrix is needed. The analysis is performed by introducing analytical and simulation models, and when both unicast and multicast traffic scenarios are considered.