Uniform weighted round robin scheduling algorithms for input queued switches

Abstract

This paper concentrates on obtaining uniform weighted round robin schedules for input queued packet switches. The desired schedules are uniform in the sense that each connection is serviced at regularly spaced time slots, where the spacing is proportional to the inverse of the guaranteed data rate. Suitable applications include ATM networks as well as satellite switched TDMA systems that provide per packet delay guarantees. Three heuristic algorithms are proposed to obtain such schedules under the constraints imposed by the unit speedup of input queued switches. Numerical experiments indicate that the algorithms have remarkable performance in finding uniform schedules.

Packet Scheduling in Switches with Target Outflow Profiles

“…The computational complexity of NPS is O(N 4 ) for an N × N switch. Rai et al [10] developed heuristic weighted round robin (WRR) scheduling policies for multiclass periodic traffic, with an online implementation complexity of O(N 3 ). More recently, Lee et al [11] proposed the Flowbased Iterative Packet Scheduling (FIPS) algorithm for periodic traffic with two classes, which minimizes the number of dropped packets when the switch is overloaded.…”