近十年隨著無線通訊越來越普遍，越來越多的使用者需要經由無線環境進行通訊，而Ad hoc網路就是熱門的通訊系統其中之一。但是基本的路由機制例如AODV、DSR等，他們並沒有提出一個機制去避免網路擁塞。當網路系統資料量過多的時候，有即時需求的資訊並無法順利傳送成功，或因延遲時間超過限制而被拋棄。因此，最近有不少相關的論文再討論如何有效的控制系統的流量，以達到資料傳輸時可以維持低延遲的品質服務保證。
　　先前論文曾提出兩種路由協定，都是根據頻寬的估測來做資料允許的控制，以提供即時性應用程式品質服務的保證。然而由於使用了過多的額外訊息封包，導致系統的效能並不能有效的提升。因此在本論文中我們提出一個具低冗餘的允許控制機制，稱為LO-QARP (Low Overhead QoS Admission Control Protocol)。經由模擬結果發現，系統流量被更有效的控制，額外的訊息封包的傳送也減少了，因此不但增加了傳送的效率，資料封包的延遲也隨之減少。

　As the wireless communication technology improves dramatically and the wireless communication service becomes more and more popular during the past ten years, more and more users like to convey their message via the wireless environment. And ad hoc network is one of the most important communication systems for the future. However, the primitive routing protocols such as AODV and DSR don’t have any mechanism to avoid network congestion. When the network loading becomes heavy, the real time data packets are unable to convey success smoothly or it may be dropped because the delay of packet exceeds delay upper bound. As a result, in order to supply QoS for real time data, many papers discuss how to control system loading recently.
　There are two routing protocols that have been proposed previously and they both utilize admission control scheme to provide QoS for real time application with bandwidth estimation. However, the improvement of performance is limited because of using too much extra routing messages. Hence we propose a low overhead admission control mechanism which is called LO-QARP (Low Overhead QoS Admission Control Protocol) in this paper. According to simulation results, we find system traffic effectively controlled and routing overhead decreased, so it has not only increased the transmission efficiency, but also reduced the delay of packet.

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