“…As VANETs play a very important role in safe http://engine.scichina.com/doi/10.1007/s11432-012-4725-1 driving, accounting management, traffic management, data communications, and vehicle infotainment, recently, much work has been done in this field, including routing protocols [32], transmission control protocols [33], and applied research [34]. Zigbee network technology is commonly used for traffic sensor networks [35] and traffic signal control system [36]. Bluetooth technology is a kind of radio technology for short-distance communication [37], which can be applied to intelligent transportation systems, parking guidance management systems, car telephones, etc.…”