6.1 結論
在車載無線網路的應用中，主要是藉由廣播訊息的方式進行車輛間通訊，而某些緊急性應 用的訊息傳輸必須要能夠即時散播且毫無延遲的傳送給其他節點，否則可能對車輛駕駛會有致 命性的影響。因此，如何選擇一條合適的路由路徑來傳輸就成為一個重要的議題，合適的路由 方法可以使路徑選擇更多元並有效的減少訊息傳輸的延遲時間。此外在實際網路環境中可能會 存在有自私節點的問題，自私節點的存在使網路的可靠度降低。基於以上兩個理由，我們應用 賽局理論提出了 Delay-Aware Routing based on Game Theory in Vehicular wireless network (DARGT)，我們所提出的方法不僅能夠有減少訊息的傳輸延遲時間，也能夠有效降低環境中 的自私行為。
最後，我們透過 NS2 模擬軟體，並於 NS2 模擬軟體中實作出 DARGT、DARGT(T)的方法，
並模擬比較我們所提出的 DARGT 及 DARGT(T)與傳統 AODV 路由方法之間的效能差異。模 擬的結果顯示，我們所提出的 DARGT、DARGT(T)在正常節點的環境下都能夠有效的降低訊 息的傳輸延遲時間，並提高封包的到達率。而在環境中存在自私節點的情況下，應用 DARGT(T) 所提出的傳輸賽局，我們能夠經由合理的獎勵與懲罰機制有效抑止環境中的自私行為，針對這 些自私節點去作處罰以減少自私行為對延遲的影響，並提高整體網路的可靠度。
6.2 未來工作
在實驗模擬中，由於我們所撰寫的 DARGT 及 DARGT(T)的程式，都是應用在高速公路 (Freeway model)場景上，並沒有考慮到在市區道路(Manhattan model)中模擬實驗。之後我們可 能可以經由建製多種不同的車輛場景檔案來進行模擬，以觀察 DARGT 在不同場景下的
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performance。並且可以切換不同的通訊標準例如 802.11b、802.11p 等等模組，看看實驗結果是 否會有不同。
此外，在我們所提出的 DARGT(T)中，我們所設計的自私節點行為較偏向於黑洞節點，缺 乏靈活的策略判斷。我們希望未來能夠藉由修改節點策略的判斷程式使自私節點的策略更靈活，
以顯現出自私節點自私且理性的特色。
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