Resequencing of messages in communication networks

Abstract

In this paper we study a message resequencing problem in a store-and-forward computer network where messages may go out of order while traversing logical channels. The logical channels are assumed to consist of multiple physical links which may be of different capacities. A message is dispatched to the fastest available link. Resequencing methods suggested in the literature [3] (resequencing at the channel level and resequencing at the virtual circuit level) are investigated for this link selection rule. The analysis is done on a two-node network connected by multiple links. The source node together with the set of outgoing links are modeled as an M/M/m queue with servers of different rates. The resequencing delay distribution and the average resequencing delay are derived. On multihop networks, the effect of message length, link numbers, link service rates, and the resequencing methods on resequeucing delay are investigated by simulation.