在無線車用網路(VANETs)中，如何快速且可靠的進行封包傳輸的繞徑是一個很重要的議題。由於車用網路快速的移動性導致車輛間通訊拓樸的連結容易隨著時間產生高度的變動，因此在處理封包繞徑的這個問題時，所面臨的挑戰將與以往的隨意行動網路(MANETs)有著很大的不同。在此篇論文中，我們提出了一個利用虛擬地標(VLs)的構想，來讓封包在車輛間進行繞徑的傳遞時，能夠有辦法得到較有根據的資料，來朝目的地前進，即使身處道路拓樸複雜、車輛密度分佈不均的環境，依舊可以找到相對有效率的路徑，且不會產生大量的封包增加網路的負擔。除此之外，我們的方法除了可以快速的將封包送達目的地，靠著虛擬地標以及通知封包的設計，也可以進行將封包從目的地送回至原發送車輛的任務，提供在車用無線網路中兩個不同位置完整的封包交換機制。

How to route packets efficiently and reliably is an important issue in Vehicular Ad hoc Networks (VANET). Due to the high mobility of vehicles, the communication topology of vehicles in VANET changes rapidly. Therefore, routing problem in VANET is very different to that in MANET environment. In this thesis, a Virtual Landmarks-based approach is suggested. Under the assistant of Virtual Landmarks, an efficient path is guaranteed even if the roads topology is complex. Our approach is applicable to routing packets between an vehicle and static destination. Simulation results shows that in comparison with previous work, our approach has much lowest
communication cost and guarantees a stable path (a path with high vehicle density).

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