Performance analysis of optical packet switches with a hybrid buffering architecture [Invited]

Feature Issue on Next-Generation WDM Network Design and Routing (WDMN) Optical fiber delay line (FDL) is currently the only technology available for implementing optical buffering. Feed-forward and feedback are two types of FDL structures in optical buffering, both of which have advantages and disadvantages. We present what we believe to be a novel architecture for WDM optical packet switches with an effective hybrid FDL buffering configuration that combines the merits of both feed-forward and feedback schemes. The core of the switch architecture is a number of arrayed waveguide gratings (AWG) and tunable wavelength converters (TWC). It requires smaller optical device sizes and fewer wavelengths and experiences less noise than feedback architecture. At the same time, it supports preemptive priority routing such as feedback architecture. Empirical results show that the proposed new switch architecture significantly reduces packet-loss probability.