Internetworking of Multiwavelength Local Optical Networks Based on a Wavelength-Tolerant Receiver Technology*

Robust-WDM is a technique to realize wavelength division multiplexed (WDM) local area networks (LANs) in the presence of laser wavelength drifts. Various medium access control (MAC) protocols have been proposed for Robust-WDM LANs. Among these protocols, the one with Aperiodic Reservation and Lenient Token-Passing control channel (the AR/LTP protocol) is the most promising. We discuss three internetworking strategies for AR/LTP Robust-WDM LANs. The aim is to explore the possibility to scale the AR/LTP Robust-WDM concepts to the metropolitan domain by looking at some basic medium-access arrangements and specifying the advantages and limitations of each. Special Remote Access Nodes (RANs) are proposed to facilitate interconnection. It is shown that by some modifications in the basic AR/LTP local area protocol and by parallel processing of connection requests, commands and control signals, the waiting time performance of a Robust-WDM interconnection can be improved. The improvement would be accomplished at the expense of some control sophistication. Further improvement can be achieved by designing a set of point-to-point links among the RANs of different Robust-WDM stars. In this case, control is relatively simplified, but the design of a RAN is made more complex and expensive.