A Study of Fairness in Packet-Switching Networks

The use of channel scheduling to improve a measure of fairness in packet-switching networks is investigated. This fairness measure is based on mean end-to-end delays derived from Kleinrock's classical model. The network designer can incorporate any desired relative delay among user classes into this fairness measure. It is found that scheduling is helpful in reallocating delay among user classes and can be used to improve the fairness of a network. It is also shown that a parameterized queueing discipline can be used to further improve fairness. A conservation theorem characterizing the effects of scheduling on overall mean end-to-end delay is established. The results are applicable to both fixed and random routing and are found to be relatively insensitive to fluctuations in traffic.