Dual-hop LANs using station wavelength routing

In future WDM local area networks, the number of available wavelengths may initially be fairly modest. As a result, spatial reuse is required in order to obtain designs which will support a reasonable number of stations. A dual-hop architecture is considered. The network is partitioned into two stages. In the first, the wavelength agility of the user stations is used to route packets from a given local optical network (LON) to a destination LON. When packets arrive at their destination LON, they are buffered and transmitted onto the required wavelength. There are a number of significant advantages to this arrangement. In addition, the proposed design takes advantage of increasingly available commercial ATM buffer/switch components. Several hybrid electro-optic designs are discussed. We propose electronic implementations for the buffering stage and also consider the "almost" all-optical approaches first introduced by Haas (1993). The performance of the proposed systems is considered using various traffic models. Simplified control strategies are also proposed and multiple wavelength sharing is used to decrease the number of required buffers.