Vehicular communications in Vehicular Ad-hoc NETworks (VANETs) play an interesting role in improving traffic flow on the roads. In such wireless networks, the vehicles cooperate with each other or with the roadside infrastructure to disseminate the data. In this paper, we introduce a mechanism based on coalitional game theory to study the cooperative transmission in VANETs. Each vehicle tries to access the Internet via gateways that can be either fixed or mobile. However, these gateways help the vehicles to access the Internet by cooperatively relaying the vehicles’ messages. Thus, two notions to indicate the availability of transmission between vehicles and gateways are introduced. These notions are chosen to deal with the highly dynamic topology in VANETs, namely the notion of an encounter and the notion of a link’s predicted lifetime. The problem is modelled as a non-transferable utility game. Then, an algorithm is proposed to dynamically form coalitions among the vehicles. Moreover, a probability of being active is set in terms of speed of the received vehicle. To evaluate the proposed solution, two scenarios are used: fixed gateways scenario and mobile gateways scenario. The numerical results show that the scenario of mobile gateways is more effective in terms of stimulating vehicles to regroup into coalitions. Hence, this helps the vehicles to access the Internet.

车辆专用网络（VANET）中的车辆通信在改善道路交通流量方面起着有趣的作用。在这样的无线网络中，车辆彼此协作或与路边基础设施协作以传播数据。在本文中，我们介绍了一种基于联盟博弈论的机制来研究VANET中的协作传输。每辆车都试图通过固定或移动网关来访问Internet。但是，这些网关通过合作中继车辆的消息来帮助车辆访问Internet。因此，引入了两个概念来指示车辆和网关之间传输的可用性。选择这些概念是为了处理VANET中的高度动态拓扑，即遭遇的概念和链接的预测生存期的概念。该问题被建模为不可转让的实用游戏。然后，提出了一种在车辆之间动态形成联盟的算法。此外，根据接收到的车辆的速度来设定活跃的可能性。为了评估提出的解决方案，使用了两种方案：固定网关方案和移动网关方案。数值结果表明，在激励车辆重新组成联盟方面，移动网关的方案更为有效。因此，这有助于车辆访问互联网。固定网关方案和移动网关方案。数值结果表明，在激励车辆重新组成联盟方面，移动网关的方案更为有效。因此，这有助于车辆访问互联网。固定网关方案和移动网关方案。数值结果表明，在激励车辆重新组成联盟方面，移动网关的方案更为有效。因此，这有助于车辆访问互联网。