A Multipath Routing Mechanism in Optical Networks with Extremely High Bandwidth Requests

In this paper, we propose to apply multipath routing in optical networks for the emerging high-performance applications with extremely high bandwidth requirements, typically larger than the capacity of one wavelength. To this end, we present a novel Multipath lightpath Provisioning mechanism and derive an optimal solution by an ILP (Integer Linear Programming) approach, with differential delay and bandwidth as constraints to multipath finding. Our mechanism can set up multiple lightpaths over multiple fiber-level paths not only to satisfy the extremely high bandwidth requirements, but also to reduce the minimum bandwidth required for backup paths as it reduces the amount of traffic affected by single fiber breaks. For comparison, we also present an ILP-based Single Path Lightpath Provisioning mechanism and show that its multipath counterpart performs better independently of the mesh topology under study. The performance results demonstrate that the proposed multipath lightpath provisioning mechanism outperforms the traditional single path routing by decreased bandwidth request blocking ratio, while reducing the amount of traffic that may be affected by single link failures.