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A mobile wireless ad hoc network (MANET) consists of a number of devices that form a temporary network operating without support of a fixed infrastructure. The correct operation of such a network requires its users to cooperate on the level of packet forwarding. However, a distributed nature of MANET, lack of a single authority, and limited battery resources of participating devices may lead to a noncooperative behavior of network users, resulting in a degradation of the network throughput. Thus, a cooperation enforcement system specifying certain packet forwarding strategies is a necessity is such networks. In this work we investigate general properties of such a system. We introduce a Prisoner's Dilemma-based model of packet forwarding and next using an evolutionary game-theoretical approach we demonstrate that cooperation very likely to be developed on the basis of conditionally cooperative strategies similar to the TIT-FOR-TAT strategy.

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This paper summarises the research on cooperative traffic information systems based on vehicular ad hoc networks. Such systems are a promising concept for exchanging traffic information among vehicles. Their application enables reductions in fuel consumption, greenhouse gas emissions and travel time. Three classes of such systems are studied: infrastructureless solutions based on inter-vehicle communication, infrastructure-based solutions relying on the peer-to-peer paradigm and infrastructure-based systems using client-server architectures. Systems within each class are briefly introduced and their strengths and weaknesses are analysed.Index Terms-Cooperative traffic information systems; vehicular ad hoc networks; intelligent transportation systems.