因為路口存在了許多不同的流動方向，在車載無線通訊網路中廣播傳輸是一種有效率的方法來傳播訊息給不同流動方向的車輛。然而，遺失封包及較差的車輛連接皆會影響傳播訊息的效率。為了解決於交通路口使用廣播機制會遭遇到的問題像是封包遺失、失去其它流動方向的傳輸，在這篇論文中，我們提出了交通路口訊息交換機制，利用換手的方式來幫忙傳播訊息以改善上述的問題。在我們的機制中，我們靠著幫忙傳輸的車輛，來幫忙我們傳播訊息給其他流動方向的車輛。除此之外，我們的論文也探討了在路口使用廣播機制的一些效能，像是端對端延遲時間 (end-to-end delay time)，封包傳輸率(packet delivery ratio)，以及訊息接收率(Message reception ratio)。我們的實驗結果將會表現出我們的交通路口訊息交換機制改善了封包傳輸率及訊息接收率。

Due to the several traffic directions at intersection, broadcast transmission is an effective approach to disseminate messages to vehicles traveling other traffic directions in Vehicular Ad Hoc Network (VANET). However, the packet loss and the poor connectivity of networked vehicles will affect the efficiency of message disseminated. To take on challenges of using broadcasting scheme to disseminate messages at intersection, in this paper, we propose a Message Handover protocol to assist message dissemination by doing handshake at intersection. In our Message Handover protocol, a potential vehicle helps to carry and disseminate the message to vehicles traveling on the other traffic direction. This paper also investigates the performance of end-to-end delay time, packet delivery ratio, Message reception ratio for using broadcast scheme at intersection. Extensive simulation results are presented to demonstrate that Message Handover improved both packet delivery ratio and Message reception ratio at intersection.

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