원문정보
초록
영어
Wireless Local Area Networks (WLANs) are becoming a popular way of networking
computer equipments in the home and office. In order to support differentiated Quality-of-
Service (QoS) in WLANs, the IEEE 802.11e Enhanced Distributed Channel Access (EDCA)
protocol allocates multiple Access Categories (ACs) with different priorities, inter-frame
spaces, and contention window sizes. This paper presents an improved Medium Access
Control (MAC) scheme to enhance the QoS of WLANs based on the idea of using the different
increasing functions for each AC to enlarge the size of contention window in the case of
transmission collision. The performance of this improved scheme under multimedia
applications is extensively investigated and compared with the original EDCA using the wellknown network simulator NS-2. The results show that this scheme is able to achieve higher
throughput and medium utilization as well as lower access delay and packet loss probability
than the original EDCA. Moreover, it provides a good prioritization level between multiple
ACs.
목차
1. Introduction
2. Existing Medium Access Control (MAC) Schemes
2.1 Distributed Coordination Function (DCF)
2.2 Enhanced Distributed Channel Access (EDCA)
3. The Improved MAC Scheme
4. Performance Evaluation and Comparison
4.1 Simulation Scenarios
4.2 Heterogeneous Traffic Models
4.3 Performance Results
5. Conclusions
6. References