LSM: 考量多重速率選擇的階層統計式路由應用於無線網狀網路中

LSM: Leveling Statistical Multi-rate Routing in Wireless Mesh Network

劉書銘(Shu-Ming Liu)

指導教授 ： 林宗男

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00470

摘要

IEEE 802.11無線網路在最近幾年中成為了最受歡迎的無線網路技術，IEEE 802.11支援了許多不同的傳輸速率(Data Rate)，因此如何去決定一個適當的傳輸速率是一個挑戰，很多文獻已經討論了速率鏈結演算法(Rate Adaptation Algorithm)的效能基於不同的測量方式，像是雜訊比(SNR)或是訊框統計值(Frame Statistics)等測量方式。802.11無線網路的效能和路徑選擇(Routing)及速率鏈結演算法的共同效應息息相關，除此之外，無線網狀網路(Mesh Network)在近幾年中發展愈來愈快速，路由的問題已漸漸浮上檯面。不同路由演算法的效能已經在文獻中討論過，然而，很少的研究是以跨層的方式來討論在無線網狀網路中路由以及速率鏈結演算法的效能。

在這篇論文中，我們提出了一個新的路由演算法，LSM，結合了速率選擇的方式來挑選最好的路徑，如此一來將可達到較高的效能。我們也在無線網狀網路中比較了不同現存的路由協定效能，以觀察出多個跳躍中(Hops)的好處。我們使用QualNet 4.0延伸我們的模擬實驗在無線網狀網路中，以不同的拓撲，不同點之間的距離來比較。模擬結果展示了每個演算法選擇路徑的能力，並且顯示出我們的演算法表現比其他演算法來的傑出許多。

關鍵字

路由 ； 速率鏈結演算法 ； QualNet ； 無線網路 ； IEEE 802.11 ； WMN

並列摘要

In recent years, IEEE 802.11 wireless networks have become the most popular wireless technology. IEEE 802.11 supports multiple transmission rates. How to determine the appropriate transmission rate is challenging. A lot of literatures discussed the performance of rate adaptive algorithms enthusiastically based on different estimations. The performance of 802.11 wireless networks depends on the joint effect of both routing paths and rate adaptive algorithms. Furthermore, Wireless Mesh Networks (WMNs) have experienced an enormous growth over the past few years. Routing issues have become more critical in wireless mesh networks. The performance of various routing algorithms has been studied extensively in the literature. However, little work has been done to evaluate the cross-layer impact of routing issues and rate adaptive problems in WMNs environments.
In this master thesis, a novel routing algorithm, LSM, is proposed which combines the rate adaptation selection to choose the best route in order to achieve higher throughput. In addition, we compare the performance of several existing routing protocols to exploit the multi-hop advantages in WMNs environments. Through extensive simulations in QualNet 4.0 under different topologies with different distances between nodes, experimental results demonstrate the ability of the existing routing protocol and show our proposed routing algorithm outperforms other existing routing protocols in WMNs environments.

並列關鍵字

Routing ； Rate adaptation algorithm ； QualNet ； Wireless Network ； IEEE 802.11 ； Wireless Mesh Networks ； WMN

參考文獻

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