Packet fair queueing algorithms for wireless networks with location-dependent errors

Abstract

Abstract-While Packet Fair Queueing (PFQ) algorithms provide both bounded delay and fairness in wired networks, they cannot be applied directly to wireless networks. The key difficulty is that in wireless networks sessions can experience location-dependent channel errors. This may lead to situations in which a session receives significantly less service than it is supposed to, while another receives more. This results in large discrepancies between the sessions' virtual times, making it difficult to provide both delay-guarantees and fairness simultaneously.Our contribution is twofold. First, we identify a set of properties, called Channel-condition Independent Fair (CIF), that a Packet Fair Queueing algorithm should have in a wireless environment: (1) delay and throughput guarantees for error-free sessions, (2) long term fairness for error sessions, (3) short term fairness for error-free sessions, and (4) graceful degradation for sessions that have received excess service. Second, we present a methodology for adapting PFQ algorithms for wireless networks and we apply this methodology to derive a novel algorithm based on Start-time Fair Queueing, called Channel-condition Independent packet Fair Queueing (CIF-Q), that achieves all the above properties. To evaluate the algorithm we provide both theoretical analysis and simulation results.

A power-aware and QoS-aware service model on wireless networks

“…If channel errors exist, the probability of a successful transmission becomes very low, and hence, bandwidth and power may be wasted during re-transmissions. Similar to [2], [13], [14], we deal with channel errors by swapping time slots from flows suffering channel errors to flows which have good channel conditions. However, we focus on minimizing the influence of channel errors on QoS and power consumption of each flow under the PBS service model.…”

On improving service differentiation under bursty data traffic in wireless networks

“…In order to provide fairness to the flows with service loss due to channel errors, a channel-condition independent fair model [14] is proposed. Under this model, each leading flow reserves a minimal fraction of service so that the degradation of service for leading flows is graceful.…”

“…The leading flow achieves graceful service degradation by dynamically adjusting the amount of compensation service based on the service credit. ACFQ uses some similar ideas to [13], [14]. However, ACFQ focuses on improving the service differentiation under bursty traffic with QoS provision.…”

“…Most previous research on fair queuing for wireless networks ( [2], [10], [11], [12], [13], [14]) focus on how to provide fair service to the flows and balance the tradeoff between fairness and system throughput. With these models, in the long run, the extent of service differentiation in terms of throughput [2], [13], [14] or time fraction [10], [11], [12] between any two flows should be approximately equal to the ratio of the service weight of the flows.…”

“…With these models, in the long run, the extent of service differentiation in terms of throughput [2], [13], [14] or time fraction [10], [11], [12] between any two flows should be approximately equal to the ratio of the service weight of the flows. However, this expectation may not be true since the extent of service differentiations also This work was supported in part by the National Science Foundation (CAREER CCR-0092770 and ITR-0219711).…”