Temporal Starvation in CSMA Wireless Networks
Cai Hong Kai, Soung Chang Liew · 2011
It is well known that links in CSMA wireless networks are prone to starvation. Prior works focused almost exclusively on equilibrium starvation. In this paper, we show that links in CSMA wireless networks are also susceptible to temporal starvation. Specifically, although some links have good equilibrium throughputs and do not suffer from equilibrium starvation, they can still have no throughput for extended periods from time to time. For real-time applications such as VoIP and video streaming, it is desirable to understand and characterize temporal starvation in CSMA wireless networks. To this end, we develop a "trap theory" to analyze the temporal throughput fluctuations. Based on the trap theory, we can develop analytical tools for computing the "degrees of starvation" for CSMA networks to aid network design. For example, given a CSMA wireless network, we can determine whether it suffers from starvation, and if so, which links will starve. Furthermore, the likelihood and durations of temporal starvation can also be computed. We believe that the ability to identify and characterize temporal starvation as established in this paper will serve as an important first step toward the design of effective remedies for it.