A network management architecture for robust packet routing in meshoptical access networks

摘要

We describe an architecture for an optical local area networkn(LAN) or metropolitan area network (MAN) access. The architecture allowsnfor bandwidth sharing within a wavelength and is robust to both link andnnode failures. The architecture can be utilized with an arbitrary,nlink-redundant mesh network (node-redundancy is necessary only to handlenall node failures), and assumes neither the use of a star topology nornthe ability to embed such a topology within the physical mesh.nReservation of, bandwidth is performed in a centralized fashion at an(replicated) head end node, simplifying the implementation of complexnsharing policies relative to implementation on a distributed set ofnrouters. Unlike a router, however, the head end does not take any actionnon individual packets and, in particular, does not buffer packets. Thenarchitecture thus avoids the difficulties of processing packets in thenoptical domain while allowing for packetized shared access ofnwavelengths. We describe the route construction scheme and prove itsnability to recover from single link and single node failures, outline anflexible medium access protocol and discuss the implications fornimplementing specific policies, and propose a simple implementation ofnthe recovery protocol in terms of state machines for per-link devices