Wavelength-routed or burst-switched optical network?

摘要

Although the quasi-static wavelength-routed optical networks(WRONs) are relatively simple to analyze and design, it has beensuggested that these may not be sufficiently flexible or adaptive to beable to respond to dynamically-varying traffic loads and servicediversity. An alternative approach, termed wavelength-routed opticalburst-switching (WROBS), assumes an obligatory end-to-endacknowledgement, and could guarantee a deterministic delay and proposesthe use of dynamically-assigned wavelengths for routing lightpaths. Herepackets at the network edge are electronically aggregated into burstsaccording to their destination and class of service (CoS) in separatebuffers on the time-scale of milliseconds, which is a typical forwardingtime of IP routers. At these time-scales the reservation of resourcesalong the path before sending the burst is feasible, allowing serviceguarantees. The two OBS approaches are described in comparison with theconceptually much simpler quasi-static WRONs, together with currentanalysis and design questions