本篇論文提出了一種基於值入軟體定義網路控制器於行動邊緣計算(MEC)架構的集中計算方法，提出了一種預測預測效益式的 k-hop車對車 (V2V) 數據卸載方法。讓兩輛行駛中的車輛 Va 和 Vb 定期使用 4G/5G 蜂窩網絡的基站 (BS) 相互通信，並定期向 MEC 服務器報告它們的資訊，包括速度、位置、方向、車輛 ID 和相鄰車輛的 ID。當 MEC 服務器內的 SDN 控制器根據提出的效用函數發現 Va 和 Vb 之間存在可行的 k-hop V2V 路徑 X 時，MEC 服務器可以通知 Va 和 Vb 啟動 V2V 卸載以卸載其數據流量到X，即他們可以直接使用X相互通信。 SDN 控制器可以基於從 MEC 服務器管理的所有車輛定期接收的回報資訊來計算和預測可能存在於兩個連續計算時間點之間的 k-hop卸載路徑。然後，MEC服務器可以（i）在X開始存在的時間點通知Va和Vb切換到比當前使用的具有更好效用的k-hop V2V卸載路徑X，（ii）修復意外損壞的k-hop V2V 卸載路徑 Y 通過尋找新的組成車輛來橋接斷開的路徑 Y 或更改為預測存在於 Y 斷開的時間點附近的潛在 V2V 卸載路徑，並且 (iii) k-hop V2V 卸載路徑結束時，找到新的 k-hop V2V 卸載路徑 Z，以便 Va 和 Vb 可以切換到 Z 以維持 V2V 卸載。即，(i) k-hop V2V 卸載的Control Plane由 MEC 服務內部的 SDN 控制器處理，以及 (ii) Datta Plane，即從 Va (Vb) 轉發數據到 Vb (Va)， k-hop V2V卸載由相應k-hop V2V卸載路徑的組成車輛Va和Vb處理，以解決車輛自組織網絡（VANET）中車輛的高移動性問題。性能評估結果表明，該方法可以提高V2V數據卸載的性能，即在跳數限制較長的情況下，具有更高的數據卸載率、更低的數據丟失率和更長的卸載服務時間。計數和低/中/高車輛密度。

This work proposed a predicted utility-centric k-hop Vehicle-To-Vehicle (V2V) data offloading method using the centralized computing approach based on the Software Defined Network (SDN) Controller inside the Multi-Access Edge Computing (MEC) server’s architecture. Let two moving vehicles Va and Vb regularly use Base Stations (BSs) of 4G/5G cellular network to communicate with each other and periodically report their contexts, including speed, location, direction, vehicle ID, and neighboring vehicles’ IDs, to the MEC server. When the SDN Controller inside the MEC server finds that there is a feasible k-hop V2V path X between Va and Vb based on the proposed utility function, the MEC server can notify Va and Vb to launch a V2V offloading session to offload their data traffic to X, i.e., they can use X to communicate with each other directly. The SDN Controller can calculate and predict the k-hop offloading paths that are able to exist potentially between two consecutive context report time points based on the reported contexts that are periodically received from all of the vehicles administered by the MEC server. Then, the MEC server can (i) notify Va and Vb to switch to the k-hop V2V offloading path X having the better utility than the currently used one on the time point that X starts to exist, (ii) repair the unexpectedly broken k-hop V2V offloading path Y through finding a new constituent vehicle to bridge the broken path Y or changing to a potential V2V offloading path that was predicted to exist around the time point that the Y was broken and (iii) find a new k-hop V2V offloading path Z when the current k-hop V2V offloading path is ended such that Va and Vb can switch to Z to maintain the V2V offloading session. That is, (i) the control plane of the k-hop V2V offloading is handled by the SDN Controller inside the MEC serve and (ii) the data plane, i.e., forwarding data from Va (Vb) to Vb (Va), of the k-hop V2V offloading is handled by the constituent vehicles of the corresponding k-hop V2V offloading path, Va and Vb to resolve the high mobility problem of the vehicles in the Vehicular Ad Hoc Network (VANET). The performance evaluation results indicated that the proposed method can improve the performance of V2V data offloading, i.e., it can have the higher data offloading fraction, the lower data loss rate and the longer offloading service time, in the situations of the longer limit of hop count and the low/medium/high vehicle density.

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