Routing With Traffic Awareness and Link Preference in Internet of Vehicles

Considering the high mobility and uneven distribution of vehicles, an efficient routing protocol should avoid that the sent packets are forwarded within road segments with ultra-low density or serious data congestion in vehicular networks. To this end, in this paper, we propose a Traffic aware and Link Quality sensitive Routing Protocol (TLRP) for urban Internet of Vehicles (IoV). First, we design a novel routing metric, i.e., Link Transmission Quality (LTQ), to account for the impact of the number, quality and relative positions of communication links along a routing path on the network performance. Then, to adapt to the dynamic characteristics of IoV, a road weight evaluation scheme is presented to assess each road segment using the real-time traffic and link information quantified by the LTQ. Next, the path with the lowest aggregated weight is selected as the routing candidate. Extensive simulations demonstrate that our proposed protocol achieves significant performance improvements compared to the state-of-the-art protocol MM-GPSR, the typical junction-based scheme E-GyTAR, and the classic connectivity-based routing iCAR, in terms of packet delivery ratio and average transmission delay.

I. Introduction

As one key component of intelligent transportation systems (ITSs), Internet of Vehicles (IoV) has attracted increasing attention recently [1]–[7], which have been developing rapidly due to the powerful push of communication and computing technologies [8]–[12]. In IoV, each vehicle equipped with a communication device functions as a portable node and/or router for other vehicles. The information can be shared among vehicles in a Vehicle-to-Vehicle (V2V), Vehicle-to-Infrastructure (V2I) or even Vehicle-to-Everything (V2X) pattern [13], as shown in Fig. 1. As a consequence, vehicles can be conductive to attain flexible and rapid organization without the limitation of service providers. Besides, large scale vehicular networks can be expected with the increasing number of vehicles. Apart from the initial design purpose, i.e., enhancing traffic safety with delay-sensitive direct broadcasting [14], [15], IoV can also offer a growing number of non-safety applications [16], e.g., mobile e-commerce and infotainment, through delay-tolerant multi-hop communication. In order to guarantee these applications, it is crucial to design an efficient vehicular routing scheme for efficient data dessimination [17], [18]. Fig. 1.

Example of three communication types.