Assessment of the IEEE 802.11e EDCA Protocol Limitations when Dealing with Real-Time Communication
Assessment of the IEEE 802.11e EDCA Protocol Limitations when Dealing with Real-Time Communication
复制标题
处理实时通信时 IEEE 802.11e EDCA 协议限制的评估
DOI：
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发表时间：
2010
影响因子：
2.6
通讯作者：
Ricardo Felipe Custódio
中科院分区：
文献类型：
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作者：
R. Moraes;P. Portugal;F. Vasques;Ricardo Felipe Custódio
分析了 IEEE 802.11e 标准中定义的 EDCA 机制的定时行为。更具体地说，本文的目标是评估 EDCA 机制（语音类别）最高优先级在支持实时（RT）通信时的局限性。 RT 通信是指以周期性间隔生成的小型数据包，这些数据包必须在消息流周期结束之前传送。否则，该消息被认为是延迟的并且发生截止期限损失。我们评估了考虑开放通信环境的 EDCA 机制，其中 RT 和非 RT 站共享相同的频段。此外，还使用现实的易错模型信道来测量干扰对无错信道的影响。我们表明，对于大多数评估场景，当使用 EDCA 机制的默认参数时，数据包丢失数量和平均数据包延迟都预测了不可接受的截止时间丢失数量。然而，如果在一组 RT 站中配置了足够的竞争窗口 (CW) 参数，则可以充分处理 RT 流量。作为本文的结论，我们提出了一些未来改善无线网络 QoS 的潜在方向。
The timing behavior of the EDCA mechanism defined in the IEEE 802.11e standard is analyzed. More specifically, the target of this paper is to evaluate the limitations of the highest priority level of the EDCA mechanism (voice category) when supporting real-time (RT) communication. By RT communication, we mean small-sized packets generated in periodic intervals that must be delivered before the end of the message stream period. Otherwise, the message is considered to be delayed and a deadline loss occurs. We have assessed the EDCA mechanism considering an open communication environment, where both RT and non-RT stations share the same frequency band. Furthermore, a realistic error-prone model channel was used to measure the impact of interferences against an error-free channel. We show that, for most part of the evaluated scenarios, when using the default parameters of the EDCA mechanism both the number of packet losses and the average packet delays forecast an unacceptable number of deadline losses. However, if adequate Contention Windows (CW) parameters are configured in the set of RT stations, it becomes possible to adequately handle RT traffic. As a conclusion of this paper, we present some potential future directions toward improved QoS in wireless networks.