Research On Data Dissemination Algorithm For Urban Vehicular Ad-Hoc Networks

VANETs (Vehicular Ad-Hoc Networks) are an important part of Intelligent Transportation Systems (ITS). The networks consist of vehicles and/or roadside infrastructures that communicate with each other to send, receive or relay messages willingly. VANETs provide protection for the safety of road traffic, and it provides more convenience for people’s travel application. VANETs are a special class of Mobile Ad-Hoc Networks (MANETs) where nodes self-organize and self-manage information in a distributed fashion. Apart from the properties of MANETs, VANETs possess a few distinguishing characteristics. These distinguishing characteristics lead to the research results of traditional MANETs cannot be directly applied to VANETs.The VANETs can implement many applications, such as traffic alert, cooperative driving, etc. Efficient and reliable data dissemination is very critical for these applications. In this paper, we analyzed the strengths and weaknesses of existing data dissemination methods. Then, we proposed a novel data dissemination algorithm for VANETs by using a topology discovery algorithm. The method regard event-driven message as topology discovery probe. We consider the following three aspects:i) the distance between two vehicles; ii) the vehicle density of its neighbors; iii) the importance of data. In addition, the paper also considers the infrastructure in the networks, and its data dissemination method is proposed. In the end of this paper, the performance of our algorithm has been demonstrated by comparison to two other recent protocols:UMB protocol and the Epidemic schemes. The simulation results show that our method can achieve better performance with higher delivery ratio and lower delivery delay. In addition, when the network infrastructure involved in the data dissemination process, the performance was improved significantly.