Architecture of Optical Burst Switched Ring Network with Distributed Fairness Control

This paper proposes an optical burst switched network architecture with distributed fairness control. Burst dropping at intermediate nodes is the weakness of the Optical Burst Switched network (OBS-n). To rectify this, the proposed architecture combines three technologies: ring structure, upstream prioritized switching (UPS), and distributed fairness control. By performing UPS on the ring, bursts are never dropped at downstream nodes. However, UPS suffers from positional priority problem in that access nodes farther from the destination have higher priorities over those closer to the destination. Therefore, to keep fairness even if the traffic is unbalanced, we apply LQF (Longest Queue First) algorithm as a distributed fairness control scheme. As a result, our architecture offers high throughput and enhanced Fairness Index of to close to 1 even if the traffic is unbalanced.