Data aggregation is a useful technology that can decrease the communication bandwidth cost in the process of data gathering in\nVANETs. However, data aggregation may lose some data accuracy. Current data aggregation schemes in VANETs only consider\nsaving bandwidth cost while ignoring the application requirement, which may result in the inaccuracy of aggregated data for\ndynamic routing application.Therefore, we propose a framework in which application demands are considered in the process of\ndata aggregation to ensure the accuracy of aggregated data for dynamic routing application.The framework consists of three parts:\nextracting QoI constraints of aggregated data, distributing the QoI-based data gathering queries, routing and aggregating data with\nQoI constraints. First, we propose average allocation method to handle the demand of single user and utilize convex optimization\nto handlemultiuser demands. Then, we distribute theQUERY message withQoI constraints in the interested area. Last, we propose\nQoI-DG protocol to do two kinds of data aggregation operation, namely, AVERAGE aggregation and HISTOGRAM aggregation.\nSimulation experiments show that our proposed method can increase about 20 percent in the collected data rate and save 15 percent\ncommunication bandwidth cost in the process of data gathering in VANETs.
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