Incentive Mechanisms in Multi-Hop Wireless Networks

this paper, we present our ongoing work on the design of mechanisms that stimulate collaboration of end users in both pure ad hoc and multi-hop cellular networks. We put the emphasis on stimulating packet forwarding, as this is one of the most fundamental services that end users should provide to each other. 2 Stimulating packet forwarding in pure ad hoc networks The absence of a trusted authority that can control the operation of the network makes stimulation of collaboration among nodes in pure ad hoc networks a very challenging problem. Our approach [2] is based on the notion of tamper resistance. One solution in this vein would be to program the correct (collaborative) behavior in tamper resistant end user devices. However, this does not seem to be very realistic, since ensuring that the whole device is tamper resistant may be very difficult, if not impossible. Therefore, we propose another approach that requires only a tamper resistant hardware module (such as the SIM card in GSM phones) in each device. We call this tamper resistant module the security module. Our assumption is that the user cannot modify the behavior of the security module. In addition, while tampering with the rest of the device is possible, our design ensures that the user cannot gain any advantages by doing s