兩層式路況系統的分析研究

Abstract

在此篇論文裡, 我們提出了兩層式路況系統的分析模型。兩層式路況系統是在兩層式架構下，藉由車子間彼此分享資訊的機制，進而取得路況資訊的系統。其中，兩層式架構是由下層的車間隨意通訊網路 (Vehicular Ad-Hoc Network) 及上層的點對點網路(Peer-to-Peer Network) 所組成。所有的車子透過主動緊急訊息廣播協定(Inter-Vehicle Communication) 組成車間隨意通訊網路，而由部份的車子透過3G等行動通訊技術組成點對點網路。我們針對在兩層式架構下作路況搜尋的效能分析。採用的搜尋效能指標包括：搜尋路況的成功率及搜尋成功情形下的平均搜尋時間。基於這種兩層式架構提出的分析模型，只需修改部分參數即可成為單純的車間隨意通訊網路的分析模型或是單純的點對點網路的分析模型。最後，我們透過模擬實驗來驗證我們的分析模型。此外；根據網路拓樸的不同，以Chord Network代表結構化點對點網路而以Gnutella Network代表非結構化點對點網路。

In this thesis, we propose an analytical model of two-tier Peer-to-Peer (P2P) Traffic Information System (TIS). This system is able to retrieve the traffic information by sharing vehicles’ local conditions using two-tier architecture that is composed of Vehicular Ad-Hoc Network (VANET) and P2P network. In the low-layer, all vehicles form the VANET via Inter-Vehicle Communication (IVC). In the high-layer, some specific vehicles form the P2P network via wireless such as WiFi or 3G. We analyze the routing performance of two-tier P2P architecture. The performance metrics include the successful rate of a search and the average latency of a successful search. Our analytical model could be an analytical mode of VANET or P2P overlay network through adjusting parameters. In addition, our analytical results are verified by simulation, and we take Gnutella and Chord as the case of unstructured P2P network and structured P2P network, respectively.