Mobile Computing

As a key component of Intelligent Transportation Systems Inter Vehicle Communication (IVC) is one of the major applications of mobile computing. A large amount of research has been carried out by academia and the industry alike in this field. IVC enables each and every high speed automobile to send, receive and forward packets amongst each other by dynamically forming mobile ad-hoc networks (MANETS). The information is transferred, distributed and acquired over this network. The vehicle to vehicle communication (V2V) enables the drivers and their vehicles to communicate with other vehicles that may not be in direct line of sight or in a multi hop network with vehicles that are even out of their radio range. Another form of communication that can be carried out by these vehicles is road to vehicle communication (RVC). This provides the vehicles access to static networks. IVC and RVC have diverse applications, like upstream traffic information to avoid road congestion to collision warnings.
This paper gives an overview of the implementation of mobile computing technology in the automotive sector. It starts with explaining the types of vehicle to vehicle ad-hoc networks and their peculiarities, and then it gives an outline of the present and future applications. The later sections discuss the types of processors and the user interfaces being used by the automotive industry to implement mobile computing applications.
Vehicle to vehicle ad-hoc networks
Ad-hoc networks are self organizing networks, where each node (an automobile which is equipped with the communication device) can act as an originator, receiver or a router for the messages being transmitted over these networks. These ad-hoc networks which are used in the automobile industry have certain specific characteristics that differentiate them from other such networks.(Tian 2002) They have high mobility as vehicles are the nodes of these networks, these results in a dynamic changing topology of the network. They can be often of a very large scale with the node density varying greatly from the urban traffic to a highway traffic environment. The mobile network nodes often have power constraints but due to ample space and power available on the automobile platform these mobile nodes have no such major restrictions. The other considerations in respect of network propagation which have to be borne in mind is that the movement of the nodes are primarily restricted to one dimension along the road geometry and the motion of these nodes can affect latency of the message delivery.(Chen 2001)
Traditional routing protocols used on the mobile ad-hoc networks (MANET) can be divided into two major categories. the single path and the multi path routing. Single path protocols such as DSDV are table driven and require the nodes to exchange information about their location. This information helps each node to update the routing tables being maintained at each node. This requires the nodes to constantly send out messages giving out their latest locations as per their change in location. In IVC based networks due to very high speeds of the nodes the topological changes of the network is very high and hence routing table driven protocols may not scale up to their requirements. The other