A study of traffic imbalances in a fast packet switch

Abstract

The performance of a nonblocking space-division packet switch is studied given that traffics are imbalanced at input and output. Analysis shows that the performance of packet queuing delay at switch input, as well as the entire throughput of the switch, can be adversely affected by such imbalances. The work is then extended to examine a transient imbalance case, where the switch experiences the alternation of two transient periods, each at a different traffic imbalance mode. The alternation is modeled by a two-state Markov chain. Both balanced and imbalanced cases can be viewed as the two extremes of the transient case. It is observed that the system throughput and the queuing performance in the transient case heavily depend on both mean sojourn time and steady-state probability at each imbalance mode.<>