Providing ubiquitous communication using handover techniques in VANET systems

Vehicular Ad hoc Networks are a long-term solution contributing significantly towards Intelligent Transport Systems in providing access to critical life-safety applications and services. Although Vehicular Ad hoc Networks are attracting greater commercial interest, current research has not adequately captured the real-world constraints in Vehicular Ad hoc Network handover techniques. This is necessary in order to provide seamless connectivity for optimal coverage and ideal channel utilization. Our previous work highlighted the challenges in providing ubiquitous communication using Road Side Unit in Vehicular Ad hoc Network. We used some of the concepts of the Y-Comm architecture such as Network Dwell Time, Time before Handover and Exit Time to provide a framework to investigate handover issues concentrating on essential parameters such beaconing and velocity of the vehicle. The results clearly showed that the Network Dwell Time was affected by frequency of the beacon and as well as the velocity of the vehicle. In this paper we conducted simulation studies to further examine the relation between these parameters along with different size of beacons. Simulation of VANET systems depends critically upon the calculation of the probability of a successful reception of a beacon or packet. The current formulas used to calculate the successful beacon reception depends on randomness and do not take into account the frequency of the beacon or velocity of the vehicle. This randomness puts a challenge for estimating the Network Dwell Time. This paper shows that these factors are significant and point to the need for a more complete analytical model for estimating the Network Dwell Time.