Nonreservation Fair Bandwidth Allocation Based on Dynamic Replacement in Optical Burst Ring Networks

Abstract

This paper proposes a real-time allocation scheme for photonic networks that use wavelength division multiplexing (WDM) and optical time division multiplexing (OTDM) technologies in the backbone and ring regional networks, respectively. A frame that is used for transferring data and control information in a ring regional network takes only one round to complete data allocation processing, instead of two rounds as required by the prior reservation scheme, so that data can be transmitted immediately. The objective is to provide max–min fair share in terms of throughput with just one round. If no free space is left on the frame, the proposed scheme allows a group (some) of the newly requested data to replace some of the already allocated data to provide max–min fair share, in terms of throughput. Data replacement and defragmentation are processed in the optical domain. Simulations show that the proposed scheme maintains max–min fair share even in unbalanced traffic scenarios. The complexity of defragmentation depends on the number of delay lines needed to regenerate the original data groups. The maximum number of delay lines is determined.