在車載網路的許多應用中，都需要公路設備至車輛端的資料傳輸協定。目前主流的公路設備至車輛端傳輸協定，是利用車輛未來的軌跡去預測封包目的地車輛的位置。然而，現存的以車輛軌跡為基礎之通訊協定並沒有考慮到車輛軌跡中途變換的行為。再者，現存用來模擬以車輛軌跡為基礎之通訊協定平台並沒有辦法模擬車輛軌跡中途變換的行為。在現實環境中，行駛中的車輛可能因為交通堵塞、駕駛習慣、交通事故以及道路施工等因素而臨時更換事先預訂之路徑軌跡。在本篇論文中，我們在現有的模擬平台上設計一套嶄新的模組，使得現有的模擬平台能夠模擬車輛軌跡中途變換之行為，並且也提供模組讓以車輛軌跡為基礎之繞送協定能夠具有適應車輛軌跡變換並對其做出因應措施的能力。我們的目的是開發一個可靠並且公正的模擬平台，讓未來車載網路中的通訊協定開發者使用。並且透過實作一個仍在開發中的可適應車輛軌跡變換行為之繞送協定，在本平台中完整的探討可適應車輛軌跡臨時變換之能力在現實道路環境下的重要性。此外，我們透過模擬平台的模組化，將通訊協定分為僅具備基礎通訊能力之協定以及因應車輛軌跡變換之措施兩大區塊，讓未來的協定開發者將可以輕易地把他們的通訊協定實作在我們的平台上並且進行模擬。在此篇論文中，我們也針對新的使用者提供了說明以及導引，幫助協定開發者未來在車載網路中進行大規模效能分析。實驗結果顯示出，與傳統的繞送協定相比較之下，一個可適應車輛軌跡變換之繞送協定將能夠在現實的環境中有突出的表現。

Infrastructure-to-vehicle (I2V) multi-hop data forwarding is a common operation required by a wild variety of vehicular ad-hot network (VANET) applications. The current approaches of I2V routing protocol use vehicle trajectory information to predict destination vehicle’s future position. However, neither did the existing trajectory-based I2V routing protocols nor the existing simulation framework consider the situation that vehicles change their future trajectory accidentally, which due to driver’s behavior, traffic jam, road construction or car accident in a realistic scenario. In this work, we accommodate the existing simulation framework to make it be adaptive to trajectory-change events. We not only developed a module to simulate the trajectory-change events of vehicles but also developed a module to handle the trajectory-change events, which the mechanism can be defined by users. Furthermore, we give the user guide and general procedures for users who want to use our framework. Simulation results show that the data delivery ratio of a routing protocol with trajectory-change handling mechanism can remain stable and outperform the others without it while trajectory-change ratio varies, which indicates trajectory-change mechanism is necessary for I2V routing protocols to be applied to a realistic scenario in VANETs.

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