<p>Packet transmission scheduling plays a key role in Quality of Service (QoS) support for real-time traffic and efficient radio resource utilization in a wireless mesh network (WMN). It is a highly complicated problem due to the fact that any scheduling decision at one mesh access point (AP) may affect the scheduling decisions in the entire network. The strict delay requirement of real-time applications makes the scheduling problem even more challenging.</p> <p> In this thesis, the packet transmission scheduling problem for real-time constant-bit-rate (CBR) traffic in a WMN is first formulated as a standard integer linear programming problem, which takes into consideration both the multihop packet transmission delay and timeline coordinations of the mesh APs. The objective is to efficiently utilize the radio resources, subject to available bandwidth of the mesh APs, co-channel interference, and packet transmission latency requirement.</p> <p>Two heuristic schemes, namely AP-based scheduling (ABS) and connection-based scheduling (CBS) schemes, are then proposed to support real-time CBR traffic. ABS makes scheduling decisions on a per-AP basis. Scheduling decisions at APs with a higher traffic load are determined before those at APs with a lower traffic load. ABS achieves close-to-optimum capacity but may go through multiple iterations before reaching a feasible solution. CBS makes scheduling decisions on a connection-by-connection basis. It gives a higher priority to connections with more hops. In CBS, connections with a lower priority can only use resources remaining from serving all higher priority connections. CBS requires much lower complexity than ABS while
achieving capacity performance slightly lower than ABS.</p> <p>We extend the proposed ABS and CBS scheduling schemes for supporting
real-time variable bit rate (VBR) traffic in a WMN. By combining the concept of
effective bandwidth and the proposed scheduling schemes, both delay and packet loss performance of the VBR traffic can be effectively satisfied. The scheduling schemes are further extended for supporting real-time traffic in a WMN with multi-radio APs.</p> <p>All the scheduling decisions are done at the time when new connection requests arrive and the results are used to make admission control decisions. In this sense, the work in this thesis is for both packet transmission scheduling and admission control for real-time traffic in WMNs.</p> / Thesis / Doctor of Philosophy (PhD)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/16770 |
| Date | 09 1900 |
| Creators | Zou, Jun |
| Contributors | Zhao, Dongmei, Electrical and Computer Engineering |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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