由於隨意網路不需要基礎建設的支持，隨意網路可以應用於許多環境。為了提升整體網路的效能，最常採用的方法是快取技術。在隨意網路中我們需要一個好的快取策略來提升效能，傳統行動計算的快取策略並不適合使用在隨意網路，因為行動計算在資料的傳遞是屬於單點跳躍的模式，隨意網路在資料的傳遞方式是透過多點跳躍方式(multihop)，所以隨意網路以合作快取的策略來討論是較好的，節點間彼此分享快取空間，更進一步提升系統效能。因為在隨意網路中節點是任意移動的，有線網路中的合作快取策略並不適合使用在隨意網路中，因為有線環境的合作快取策略，是基於穩定環境的條件下設計的。由於上述兩點，我們需要在隨意網路中，找出更好的合作快取策略提升系統效能。
由於目前隨意網路中所提出來的合作快取策略中，並沒有以考量每個節點剩餘的能源，如此很可能會產生過度的使用某些節點的狀況，造成縮短某些節點的生命，導致整體網路的完整功能運作的時間縮短，縮短了網路生命時間。因此我們提出了考量能源的合作快取策略，避免過度使用了某些節點的能源，以達到延長網路生命的目的，模擬實驗的結果說明我們的合作策略確實能延長網路的生命時間，並且降低了一些請求延遲，以及提高了資料可獲得性。

Because Mobile Ad Hoc Network(MANET) does not need any infrastructure to support, it can be applied in many environments. In order to increase system performance, data caching is a useful technique. In MANET we need a better caching policy to further improve system performance. Mobile Computing caching policy may not be applicable to MANET. Because Mobile Computing environments is client server model, they communicate with each other using single hop. In MANET nodes communicate with each other using multihop relay. Therefore in MANET it need using cooperative caching concept to design caching policy. Cooperative caching concept, node share cache memory space with each other to further improve system performance. Cooperative caching techniques designed for wired network may not be applicable to ad hoc networks. Since in MANET mobile node move freely, it is unstable environments. Therefore we need design cooperative caching policy to further improve system performance in MANET.
Because relative cooperative caching policy does not consider node leave energy. When we design caching policy, if we do not consider energy then it may be overuse some node. Therefore some node may die early and it may lead to reduce complete networks function time. That means it will reduce network life time. Therefore we propose caching policy that consider node energy to avoid overusing some node in order to prolong the network life time. Simulation result shows that the method we propose can prolong network life time and reduce query delay and increase data accessibility.

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