Photonic Label Switch Supporting Asynchronous and Variable-Length Packets

In this paper, we propose new optical switching archi-tectures supporting asynchronous and variable-length packets. Output line contention is resolved by optical delay line buffers. By introducing a WDM technology, parallel buffer can be equipped with multiple wavelengths on the optical delay line buffer. Differently from existing approaches, a main feature of our proposed architecture is that by employing a ultra-fast photonic label processing tech-nique, an implementation is realistic for packet scheduling, which selects the appropriate output port, wavelength and delay line buffer. For evaluating the switch performance, an output port of our proposed switch is mo deled as a multi-server and multi-queue system where each server corresponds to the wavelength. The arriving packet joins the shortest queue according to the scheduling policy of our switch. The switch performance is studied by utilizing an approximate analytic approach. Through the analysis and simulation experiments, we show that the introduction of the WDM technique can much improve the switch performance in terms of packet loss probabilities. 1