A New Information Propagation Scheme for Vehicular Networks
Thomas D. C. Little, Ashish Agarwal · 2005
A goal in Vehicular Ad hoc Networks (VANETs) is to enable the dissemination of traffic and road conditions such as local congestion and surface ice as detected by independently moving vehicles sometimes called Information Warning Functions (IWF) [1]. Enabling data propagation in a VANET is challenging due to the existence of partitions between nodes described as network fragmentation. Existing routing protocols are based on the formation of an end-to-end path between source and destination or rely on a naming scheme and few exploit the mobility of nodes in a VANET. Resource discovery and naming are problematic under the presence of frequent and rapid arrivals and departures. Related work on this problem is designed to provide Internet services to vehicles through the use of roadside access points which bridges local VANETs to achieve connection-oriented traffic. In this work, we focus on providing IWFs without the use of fixed infrastructure such as access points or satellite communication. We propose a new scheme called Directional Propagation Protocol which is based on the concepts of custody transfer mechanism adopted from Delay Tolerant Networking (DTN) research, cluster formation and the use of attribute based data from MANET methodologies.Each is described next. Clustering: Vehicles on directed pathways that are within symmetric communication range of one another form interconnected blocks of vehicles as shown in Fig. 1(a). Clusters are defined as groups of nodes that form within blocks (blocks can be comprised of multiple clusters traveling in the same direction). There are many techniques for cluster formation; we adopt the technique of Lin and Gerla [5]. Each block has a header and trailer node located at the head and tail of a cluster respectively, that perform the message transmission