In-advance path reservation for file transfers In e-Science applications

We develop multi-path reservation algorithms for in advance scheduling of large file transfers in connection-oriented optical networks. Specifically, to schedule a single file transfer to complete at the earliest possible time, a new max-flow based greedy algorithm (GOS) and four variants that adapt the k shortest paths and k-disjoint paths algorithms are proposed. Meanwhile, to find an earliest-finishing schedule for a batch of file transfers, a linear programming based algorithm (BATCH) is developed. Extensive experiments using both real world and random networks show that our GOS algorithm provides a good balance among maximum finish time, average finish time, and computational complexity. Although our BATCH algorithm results in the smallest maximum finish time, this algorithm has a significantly larger computational requirement than our other algorithms. GOS yields file transfer schedules with similar maximum finish time and reduces average finish time while having a significantly less computational requirement.