Sequential Task Anycast Scheduling in Optical Burst Switched Networks

We investigate the sequential task anycast scheduling problem (STAS) for grid applications in an optical burst switched network. In STAS, the subtasks of a given request have sequential dependency and must be processed in order. Each node in the network provides a set of services and each subtask may demand a different type of service. The problem is to find an ordered set of nodes that can minimize the request completion time and request blocking probability. In this work, we consider the delay caused by buffering at service nodes and the blocking caused by burst contention. We propose an auxiliary graph based heuristic with cost assignment policies to obtain ordered set of sequential nodes which can minimize task completion time. We compare the heuristics with a random task assignment policy, and the results show that the proposed heuristics can improve request blocking probability and end-to-end delay.