Robust routing for local area optical access networks

One approach to providing the benefits of the high data rates afforded by optics is to attempt to implement traditional electronic and electro-optic approaches using optical technologies. In electronics, operations such as buffering, adding packets and dropping packets, or merging packet streams, are done with ease. In optics, however, buffering is onerous. Operations such as retrieving a packet from a traffic stream affect the whole stream. The routing approach we propose seeks to make use of the strengths of optics and avoids operations that are cumbersome or expensive in optics. Our goal is to provide robust and reliable approaches to access at optical data rates. Our design rationale is the following: avoid buffering; do not use a switch unless necessary; and, use the optical layer to provide recovery. We describe a routing such that recovery is possible even in the event of any link failure. Our routing consists of two parts: a collection portion and a distribution portion.