Fast and versatile scheduler design for optical packet/burst switching

Abstract

The most promising solutions to increase bandwidth efficiency in IP over DWDM networks are represented by Optical Packet and Burst Switching. Due to the statistical multiplexing approach adopted, these paradigms must deal with packet/burst contentions at the node output channels and require the use of scheduling algorithms to optimize resource assignment and bandwidth utilization. However, very strict time constraints on the scheduling operations are imposed by the extremely high bit rates used, making the actual feasibility of the scheduler control logic a major implementation issue common to both technologies. This paper provides a specific formulation of the scheduling problem that can be used as the basis for the practical design of a fast and versatile scheduler, capable of implementing many algorithms found in literature. A possible implementation of the scheduler sub-functions, mainly based on the use of combinatorial operations, is also discussed and supported by the simulation of the hardware implementation time response, with results that demonstrate the feasibility of the proposed solution.