在5G 的世代裡，傳統使用回傳到核心網(core network) 的傳輸方式已經無法負
荷如此大量的數據，為了讓人們快速且方便獲得所需的資料，除了使用設備到設
備的傳輸(Device to Device ;D2D)，利用邊緣緩存的想法將流行的文件存放於本
地的設備或基地台也是能夠提升快速獲取資訊的方法，同時也能解決回傳的負
擔。在本論文中，我們設計一套連線選擇模式，並且使用” 最小延遲連接” 法作為
用戶與傳送文件裝置的連線條件，透過這個方法，在具有儲存功能的D2D 用戶
和有儲存功能的基地台(Fog access point; FAP) 環境中分析用戶在各種裝置中取
得文件的機率與所花費的延遲。就結果而言我們確實能降低總延遲，邊緣緩存也
幫助我們有效率的在本地找到文件。

In the 5G generation, the traditional transmission method back to the core network
can no longer load such a large amount of data. In order to allow people to quickly
and conveniently obtain the required file, in addition to using the device to device
(D2D) transmission, using the idea of edge caching to store popular files in a local
device or base station is also a way to improve quick access to information, and it can
also solve the burden of backhual. In this paper, we design a connection selection
mode and use the ”minimum delay connection” method as the connection condition
between the user and the file transmission device. Through this method,we analysis
the content hit probability and the delay in the environment of the cache-enabled
D2D user and the the Fog access point (FAP) . In terms of results, we can indeed
reduce the total delay, and edge caching also helps us find files locally.

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