Dynamic routing-tree based data forwarding scheme for urban vehicular ad hoc networks

Vehicular ad hoc networks (VANETs) are expected to be used in many aspects ranging from road safety applications to commerce promotion and interactive services. Although data forwarding has been extensively addressed, some unique characteristics of VANETs offer new research interests. This paper presents a dynamic Routing-Tree based Data Forwarding (RTDF) scheme, which focuses on road networks with a static hotspot. The hotspot will broadcast messages to build a routing-tree to provide data delivery routes for vehicles if it receives more than a certain number of inquiries during a period of time. The certain number is calculated through an analytical packet delivery overhead model. The routing-tree can be dynamically maintained by each intersection. We suppose this scheme can provide minimum delay routes for vehicles with fewer packets delivery overheads compared to that of letting vehicles discover routes themselves, and some simulations are performed to verify this belief. Extensive simulations will be done in future work to verify other performance metrics.