Delay-bound preservation through packet scheduling at wireless access point nodes

Wireless packet schedulers have concentrated for the most part on preserving fairness in a network environment where channels are subject to location-dependent errors. By recording the lost service and compensating flows after an error period, long-term throughput and long-term fairness can be maintained. This paper stresses that what is most pertinent to current wireless QoS however, is the preservation of delay guarantees for sessions in the face of channel errors. A traffic profile and priority based wireless fair queuing (TPP-WFQ) scheduling approach is proposed, which utilizes all available residue bandwidth in the system to allow sessions to catch up to their error-free service as quickly as possible. In addition, a bandwidth management platform that adjusts session weights for use by the scheduler is presented. Priority is given to real-time traffic with strict delay bounds for both bandwidth utilization and compensation. Simulated results illustrate how maintaining short-term delay guarantees in this way does not affect long term fairness and throughput guarantees for other sessions more tolerant to delay.