在無線隨意網路中利用拓樸控制達成品質服務路由之研究

Topology-aided and Load-aware QoS Routing (TLQR) in Wireless Ad Hoc Networks

孫憲平(Hsien-Ping Suen)

指導教授 ： 周承復

國立臺灣大學/電機資訊學院/資訊工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.02947

摘要

近幾年來，由於無線傳播技術的快速發展，日常生活中的無線科技應用愈來愈頻繁，
人們的生活也因此愈來愈便利。無線隨意網路(Wireless Ad Hoc Networks)是由許
多無線節點(Wireless Node)依其本身的需求，動態組成的網路；各個無線節點可以任
意加入或離開無線隨意網路，整體網路的佈署也可以在任意時間任意地點完成。由於無線
隨意網路的便利性，先前已被廣泛應用於戰場以及急救場所的通訊；隨著無線網路的普及，
未來更可應用在研討會議室或展覽會場內，提供多媒體的服務。
許多的網路應用需要相當程度的傳輸品質提供網路連線，例如視訊與語音的服務，必
須有足夠的頻寬與有限的資料延遲，才能達成合理的使用品質；為了能提供可保證的傳輸
品質，整體網路所付出的代價往往是較低的同時使用人數。在這篇論文中，我們藉著計算
每個無線節點的可傳輸量，提出一個建立路由的機置，保證所有已建立的連線有足夠的傳
輸頻寬可供使用；再者，我們利用調整每個無線節點的傳輸功率，試圖減少每個無線節點
之間的干擾，藉此提升整體網路的使用效能，增加同時使用的連線數目。
我們利用程式模擬多種網路環境，對於我們所提出的機制加以評量。實驗結果顯示，
在絕大多數的模擬環境下，利用計算可用頻寬以幫助建立路由的方式，可使整體網路的使
用效率增加7%~25%，結合計算可用頻寬與適度調整傳輸範圍的機制，則可使整體網路的
連線接受率增加14%~39%。

關鍵字

無線 ； 網路 ； 隨意網路 ； 拓樸控制 ； 品質服務 ； 路由

並列摘要

In recent years, the convenience of wireless networks has been brought into our daily lives, and
there are many network applications like media conferencing requiring guaranteed qualities
such as bounded delay and minimum bandwidth. To ensure the quality of each communi-
cation in a wireless ad hoc network, the number of concurrent connections may not be very
large. It will be a challenge to maximizing the ad hoc network utilization while guaranteeing
the quality of service (QoS) at the same time.
In order to satisfy the required end-to-end bandwidth of each communication in wireless
ad hoc networks, we provide a distributed admission control scheme to determine whether a
wireless node is capable to relay data for others. We estimate the capability of transmission
of each wireless node when the node receives a routing message. In this way, we can establish
better routes to make communications with QoS support.
Furthermore, we try to make the spacial reuse better to maximize the utilization of a
wireless ad hoc network. There are many researches showing that if the transmission range
of each wireless node is properly assigned, the total amount of network throughput can be
improved dramatically. We dynamically adjust the transmission range of each wireless node
when the local tra±c condition changes, so that we can adopt more connections in this
network.
The experimental results show, by simply applying the admission control mechanism
on the naive °ooding routing, we can improve the total amount of end-to-end throughput
around 7{25%; and the improvement can be further achieved about 14{39% if we apply the
admission control scheme and the transmission range adjustment mechanism simultaneously.

並列關鍵字

topology ； load-aware ； qos ； routing ； tlqr ； ad hoc ； networks

參考文獻

[1] Theodore S. Rappaport. Wireless Communications: Principles and Practice. Prentice

[2] David B. Johnson and David A. Maltz. Dynamic source routing in ad hoc wireless

networks. In Imielinski and Korth, editors, Preceedings of Mobile Computing, volume

353. Kluwer Academic Publishers, 1996.

[3] Dharma Prakash Agrawal and Qing-An Zeng. Introduction to Wireless and Mobile