Timescale analysis for wavelength-routed optical burst-switched (WR-OBS) networks

Abstract

The relationship of three timing parameters in the WR-OBS network architecture has been identified and investigated, to quantify the limits on the operation of a dynamic network. An adaptive burst assembler at the network edge provides an accurate estimation of the maximum edge delay whilst preventing buffer overflow, depending only on the mean and variance of incoming traffic. The round-trip time defines the achievable wavelength re-use under dynamic network operation, which could be as large as 20 for the example shown. The processing and queueing latency in the network control node links all three parameters and imposes a lower bound to the edge delay for a given number of edge routers. The unlimited burst size (UBS) scheme not only overcomes the main limitation of many OBS approaches-excessive burst loss for high network loads, but also reduces latency with increasing load, potentially ensuring adaptive network operation over a wide range of loads.