Distributed Router Architecture for Packet-Routed Optical Networks

A new proposal for an optical packet-routed network based on a distributed router architecture in a WDM network is described. Buffering, scheduling and wavelength assignment functions are carried out in routers located at the edge of the network. The destination address is encoded by a given wavelength and allows wavelength-routing in optical core routers. This approach avoids processing and additional buffering delays in core routers. A low packet loss rate and a low latency are critical parameters to guarantee QoS for a particular class of packets and must be carefully considered when IP traffic is directly transmitted over a photonic network. This network architecture requires new hardware elements and these are discussed including a low-crosstalk, large port-count free-space grating router.