Optical burst switching networks for next generation optical internet

Abstract

Optical burst switching (OBS) is an approach to building very high capacity routing techniques based on optical data paths and electronic control. Therefore, OBS is considered as a viable solution in high-speed WDM backbone. In this paper, we describe the design issues for OBS core and edge node, such as control and data plane architecture, and contention resolution, QoS guaranteed mechanism, and optimal burst size decision scheme. The existing QoS mechanisms for optical level support not the $\emph{quality of service}$ (QoS) but the $\emph{class of service}$ (CoS), provisioning of QoS guaranteed performance in OBS should be attractive especially for IP-over-WDM applications. The $\emph{dynamic wavelength management}$(DWM) based QoS guaranteeing mechanism is studied in details. This mechanism guarantees a required level of blocking loss rate and limits the maximum delay. In addition to QoS mechanism, we consider the contention resolution scheme. OBS has inherently high blocking loss rate, since the buffer is not mandate in core node. The performance results of the contention resolution scheme using alternative routing efficiently work at the intra-class contention. Finally we discuss about the optimum size of data burst which effects the network performance directly.