無線隨意網路(MANET)提供了一個不需要基礎建設的網路環境，適合用於臨時需要網路通訊但卻無基礎建設的情況，像災區救難、戰地通訊等。為了提昇網路整體的效能，常採用資料快取(data caching)技術。但只要環境下的資料會隨著時間的改變而異動，就必須要把資料一致性(data consistency)的議題納入考慮。傳統行動計算網路環境中對備份資料一致性維護方法並不適用於無線隨意網路環境，這是因為傳統行動計算網路中資料的傳遞屬單點跳躍(single-hop)，亦即網路中各節點(mobile nodes)可以直接傳到伺服器，不需要靠其他節點的傳遞，若有節點所要求的資料被異動，可以很迅速的和伺服器來索取最新的資料內容。
而無線隨意網路中，使用的是多點跳躍(multi-hop)的傳送方式，節點與伺服器之間，經常需要靠多個節點傳遞方能傳送資料，無線隨意網路的連線也不是非常穩定，各節點之間連線時常斷線，向伺服器取得最新資料並非有效率的方式，轉向鄰近節點取得最新的備份資料內容是比較可行的方式。故本研究除了快取備份策略之外，還把資料驗證的方法融入，達成一個有效率的快取搜尋策略，讓網路中的節點可以快速的尋獲最新的資料。在無線隨意網路中的快取一致性和快取管理議題上，我們提供了一個資料搜尋策略，減少能源浪費同時能夠快速的獲得最新資料。模擬的結果顯示，我們所提的方法不但減少了能量消耗也縮短了查詢回應時間。

A Mobile Ad Hoc Network (MANET) is a wireless network which does not need any pre-existing infrastructure. A well-known approach to improve the communication performance of a MANET is to cache the required data items. With cooperative caching, a mobile node caches data items not only for itself but for other nodes which are also interested in the same data items. If the data items in the networks are allowed to be updated, we need to maintain the consistency of the cached data items.
In this paper, we propose a cache scheme, called belt-shaped region cooperative cache scheme, which includes a cache search strategy, a caching strategy and a consistency-maintaining strategy. In this scheme, we design a new approach to cache data items so that the server can spend minimal cost to maintain the cache consistency and the mobile nodes can find their required data efficiently. This approach reduces the mean distance from a requesting node to the replying node for accessing a required data item. The simulation results show that our approach outperforms the existing methods, such as ACOD and MTS, in terms of query response time and energy consumption.

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