Ultrafast photonic label switch for asynchronous packets of variable length

This paper describes new optical switching architectures supporting asynchronous variable-length packets. Output line contention is resolved by optical delay line buffers. By introducing a WDM technology, a parallel buffer can be equipped with multiple wavelengths on the optical delay line buffer. Using an ultrafast photonic label processing technique, an implementation of our architecture would be fast enough for packet scheduling that selects the appropriate output port, wavelength, and delay line buffer. To evaluate the switch performance, we model an output port of our switch as a multi-server and multi-queue system where each server corresponds to a wavelength and where each arriving packet joins the shortest queue. We use an approximate analytic approach to evaluate the switch performance. The results of the analysis and of simulation experiments show that the use of the WDM technique can greatly improve the switch performance in terms of packet loss probabilities.