Real-time traffic management on optical networks using dynamic control of cycle duration

This paper proposes a new approach to real-time traffic management over a multihop optical network. Unlike the current preemption-based real-time traffic scheduling approaches (where, the QoS of the preempted traffic may suffer significantly), the proposed approach is based on dynamic creation of logical channels to support new arriving real-time messages. The logical channels are mapped to the TWDM (time-wave division multiplexed) transmission schedule of the optical media. Since, the new logical channels can support the fresh arrival of real-time messages, it may no longer be necessary to preempt an existing message. This feature offers significant QoS benefits to the existing traffic. The price paid for creation of the logical channel(s) is via an extension of the cycle time in the TWDM transmission schedule. Such extension of the cycle time imparts a uniform degree of slowdown to all the existing channels, and enforces excellent load balancing. A state machine model for dynamic control (i.e., extension, and/or shrinking) of the TWDM transmission schedule is proposed. Performance is measured using simulation.