行動隨意網路(MANET) 是一個由無線行動節點所組成的動態無線網路，在行動隨意網路下無需固定的基礎建設且行動節點有自我組態的特性，近年來有相當多的研究及其應用。由於在行動隨意網路下沒有固定的基礎設施提供節點資訊或資訊的傳遞，換句話說，節點間只能夠在彼此的通訊範圍內做區塊的傳遞，而行動隨意網路動態網路拓墣的特性造成節點通訊範圍內的鄰居時常的變更，可能造成節點間在區塊傳遞的選擇上是沒有效率的，因此節點間如何選擇一個適合的區塊做傳遞來達到節點收集區塊速度的提升是一個重要的議題。
網路編碼(Network Coding) 是一種可以對區塊做編碼的技術，而網路編碼在多點傳播的網路環境下能夠有效的降低節點間冗餘的傳輸次數。在本篇論文中，我們在行動隨意網路中讓節點利用XOR 的網路編碼方式對區塊做編碼，並且限制節點只能夠對兩個區塊編碼，利用此種編碼規則來改進網路效能。在上述條件下接著我們提出了一個最大開放性的區塊傳播策略，最大開放性的方法能夠有效的提升節點接收到有用的區塊之機率，藉此在行動隨意網路時常改變網路拓墣造成節點難以掌握通訊範圍內鄰居所擁有區塊的情況下，節點也能夠利用最大開放性的方式來達到有效率的收集區塊的目的。
在我們的模擬中，我們去比較最大開放性和稀有優先在節點收集完區塊平均時間上的效能。透過模擬的結果顯示，我們提出的方法平均在節點收集完區塊的時間上約有10% 的改進。

A Mobile Ad hoc Network(MANET) is a self-organizing and infrastructureless wireless network composed of mobile nodes. Due to the dynamic topology of mobile nodes, these nodes are difficult to know neighbors’ information and inefficient to choose a block to transmit. It is an important issue for a node to use less number of communiations to enhance the speed of collecting blocks. Network coding is a technology to encode blocks and efficiently reduce the number of redundant transmission with nodes in multicast. In this paper, we allow nodes to take advantage of XOR-based network coding to encode blocks. Moreover, each node can only encode two blocks. Therefore, we propose a Maximum-Openness strategy to disseminate blocks. In Maximum-Openness, the probability of a node to receive useful blocks can be higher increased. In our simulation, we compare Maximum-Openness the average time of blocks collecting with Rarest-First. Experimental results show that the average time of blocks collecting increased by 10% as compared to Rarest-First.

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