Utility-based fair bandwidth sharing in vehicular networks (extended)

The time-constraint data traffic is very common in vehicle-to- infrastructure (V2I) and vehicle-to-vehicle (V2V) communications. Time-constraint flows are those who have fixed start and stop times and try to maximize the transferred data volume during the limited connection time. From the view of users, the total data transmitted by each flow should be proportional to each one's holding time if the network resources are allocated fairly. However, we find that the traditional fairness concept solely based on flow rates is not suitable for this scenario. Therefore, we redefine the fairness concept regarding the application utility for time-constraint flows. According to this new utility-based fairness definition, we propose two practical bandwidth sharing schemes for transferring data by fast-moving wireless nodes such as vehicles. Simulations through ns-2 show that the proposed algorithms can achieve better utility fairness than the standard TCP and are also friendly to TCP in the long term.