Optimal Utilization with Fairness and Priority Considerations in Optical Networks Based on Light Trail

In this paper we consider unidirectional optical busses that originate at a convener node and end at a terminator node. Nodes can transmit only to nodes that are farther downstream, hence the convener node can not receive any bus traffic and the terminator node can not place any information on the bus. The bus supports both data traffic which is bursty as well as connections between source to destination pairs. We assume there exists a control channel outside of the bus that lets the terminator node send information to the convener node. We propose a cycle based protocol where in each cycle all nodes send their requirement to the terminator node which then sends out estimated requirements via the convener node. Then in a distributed computation individual nodes compute their utilization for that cycle based on their priority while paying attention to fair allocation for itself and other nodes. In the process a node may adjust its priority above or below the predicted value. Using simulation we evaluated of the capacity fairness and preemption fairness per node under the constraint of maximum access delay.