FairNet: a WDM-based multiple channel lightwave network with adaptive and fair scheduling policy

An efficient and fair access scheme, called FairNet, by which a number of parallel channels can be shared among a number of nodes, connected by an optical bus-based structure. The network consists of N nodes and W parallel channels. All the channels are slotted and synchronized and the slot length equals the packet transmission time. Since high-speed interfaces are expensive and since optical signal strength reduces with the number of taps, only a small number of transmitters and receivers are used. Specifically, each node is equipped with a tunable transmitter which can be tuned to any of the W channels, a fixed receiver which can receive from a preassigned channel, and a tunable sensor. Network operating parameters for various fairness criteria (e.g., equal average packet delay at each node) are analytically obtained using both exact and approximate approaches. To adapt to the fluctuations (if any) of the offered loads at various nodes, the transmission probabilities can be dynamically adjusted