Enhanced VANET broadcast throughput capacity via a dynamic backbone architecture

We propose a high throughput dissemination scheme for Vehicular Ad Hoc Networks (VANET) based on the dynamic formation of a multi-hop backbone network. We describe and analyze such a networking protocol when used to broadcast message flows generated by a Road Side Unit along a linear road, forming a VANET structure that is identified as a Vehicular Backbone Network (VBN). The VBN is based on elected vehicles that reside at preferred locations to act as backbone relay nodes, jointly optimally configured to operate at designated link data rates and spatial reuse factors. We present both an analytical evaluation of the broadcast throughput capacity that can be achieved by using the VBN mechanism and a simulative analysis based on the IEEE 802.11p CSMA/CA MAC protocol, standardized for VANET. The results demonstrate the significant performance enhancement achieved under VBN in attaining enhanced throughput capacity rate and in providing for a wider dissemination coverage span. Admitted packets are assured low end-to-end packet delays through the employment of a flow control scheme.