Cross-layer communications for high-bandwidth optical networks

A major challenge in meeting the enhanced performance requirements of next-generation optical networks is overcoming the rigid limitations due to network layering. Our work addresses this issue by creating a bidirectional cross-layer communications infrastructure that can leverage knowledge of the optical-layer performance to improve network performance. The goal is to create an intelligent, dynamic, and programmable optical substrate where optical performance monitoring measurement data can be used for cross-layer communications, specifically for network routing and packet protection. Ns-2 simulations show that a cross-layer proactive packet protection scheme using physical-layer bit-error rate measurements performs better than a fast-reroute mechanism in terms of packet loss rates. Further experimental demonstrations of the cross-layer communications infrastructure on an optical packet-switching fabric test-bed can also incorporate the optical packet´s signal degradation and quality-of-service class to switch and reroute messages. We can then realize a quality-of-service-aware cross-layer network control framework that is based on emerging optical performance monitoring devices for next-generation optical networks.