目前，隨著技術和硬體的快速發展，行動裝置已經成為人們日常生活的一部分。雖然LTE行動網路已經穩定發展，可以支援行動裝置的大規模通訊服務，但核心網路和行動裝置的流量分流仍然是一個問題。此外，行動裝置之間的頻繁碰撞也是一個問題，因為它們需要競爭有限的網路資源。行動邊界計算（Mobile Edge Computing，MEC）是一種應用於網路邊界並且還在發展中的技術，它可以協助位在網路邊界的行動裝置卸載行動網路流量，並在發送到核心網路之前透過向遠程MEC傳送資料來減少巨大的計算工作量, 並減少應用程式之間的延遲時間。為了解決流量和位置問題，本文提出了MEC協助裝置對裝置通訊分流（MD2DO）的通道選擇機制，可以確定行動裝置的位置，並透過通道選擇的機制有效地進行Wi-Fi D2D來達到流量分流。實驗結果顯示，MD2DO透過有效率的通道選擇減少了行動裝置之間的碰撞，提高了網路效能。

Nowadays, with rapid development of technology and hardware, mobile devices have become an important part of people’s daily life. Although LTE (Long Term Evolution) had been developed stably and can support large scale communication services to mobile devices, the traffic offloading in core network and mobile devices is still an issue. Besides, the intensive collision between mobile devices is also an issue because they need to compete the finite network resources with each other. Mobile Edge Computing (MEC) is a promising technique applied to network edge, which can assist the edge device to offload the data traffic and decrease the gigantic computation effort through sending the complicated tasks to remote MEC before sending to core network. To solve the traffic and location issues, this paper proposed a channel selection scheme for MEC-assisted Device to Device communication Offloading (MD2DO) which can help the peered mobile devices to confirm the location of the mobile device and efficiently have Wi-Fi D2D through channel selection for traffic offloading. The simulation results proved that the MD2DO method decreases the collisions between the mobile devices through the efficiently channel selection and enhances the network performance.

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