此篇論文提出一種以網路編碼競爭為基礎的協定用於增加網路編碼的效能。Sachin Katti 等人提出一個命名為COPE的實作網路編碼系統。它是利用無線網路的廣播特性結合網路編碼技術來增加網路效能。目前為止已經有一些研究針對COPE的效能去進行分析與研究，但只有極少數的論文能夠提出有效的辦法來增加網路編碼的效能。網路編碼技術可以應用在高負載的網路環境裡面，但是大量的封包傳送容易提高碰撞的機會導致整個網路的產出低落。此篇論文提出一個網路協定方式增加網路編碼的效能。此協定包括了三個主要機制，包括了節點內的競爭(intra-node contention)、節點間的競爭 (inter-node contention)和以編碼為基礎的競爭傳送機制 (coding-based contention forwarding)，來提高封包在傳送過程中的編碼機會。此篇論文也考慮到不同種類的網路封包特性，以適應在大型無線網路系統如網宇實體系統中。而實驗結果顯示此篇論文所提出的以編碼為基礎競爭傳送協定可以有效的提升整個網路的產出。

This thesis proposes a contention-based protocol on network coding technology in order to increase network coding performance. A network coding system named COPE was proposed and implemented by Sachin Katti et al. It exploits the physical-layer broadcast nature and network coding technique. There are already some researches that focus on estimating the performance of COPE and propose methods to improve it. However, there is no effective way able to increase the network coding throughput. Network coding technique can be applied in a high-traffic network environment, but enormous transmissions lead to high collision rate. This thesis presents a protocol with three mechanisms to enhance the efficiency of network coding. By applying intra-node contention, inter-node contention and coding-based contention forwarding, a packet can obtain more coding opportunities from the source to the destination. This system also considers different access categories issue to adaptive to a large wireless environment, such as Cyber-Physical System. Simulation result shows that coding-based contention forwarding protocol can significantly increase throughput in a network coding network.

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