Journal of Communications and Information Networks
Print ISSN 2096-1081 CN 10-1375/TN
Editor-in-Chief: Wei Zhang
In recent years, IoV (Internet of Vehicles) has become one of the most active research fields in network and intelligent transportation system. As an open converged network, IoV plays an important role in solving various driving and traffic problems by advanced information and communications technology. We review the existing notions of IoV from different perspectives. Then, we provide our notion from a network point of view and propose a novel IoV architecture with four layers. Particularly, a novel layer named coordinative computing control layer is separated from the application layer. The novel layer is used for solving the coordinative computing and control problems for human-vehicle-environment. After summarizing the key technologies in IoV architecture, we construct a VV (Virtual Vehicle), which is an integrated image of driver and vehicle in networks. VVs can interact with each other in cyber space by providing traffic service and sharing sensing data coordinately, which can solve the communication bottleneck in physical space. Finally, an extended IoV architecture based on VVs is proposed.
Connected vehicles are promoted with the use of different communication technologies for diverse applications and services. There is an ongoing debate in the research and industry communities whether short range communications based on IEEE 802. 11p or cellular based on 3GPP LTE should be used for vehicular communications. We propose a mechanism to utilise both short range and cellular communications simultaneously in a cost efficient way while providing the required quality of service to the users. A host connected to multiple networks is referred to as a multi-homed node and SCTP (Stream Control Transmission Protocol)is an IETF standard which supports multi-homing. We propose an extension to SCTP that takes into account not only path quality but also the cost of using each network. It is shown that the combination of QoS and cost information increases economic benefits for provider and end-users, while providing increased packet throughput.
In vehicular networks, the exchange of beacons among neighboring vehicles is a promising solution to guarantee a vehicle’s safety. However, frequent beaconing under high vehicle density conditions will cause beacon collisions, which are harmful to a vehicle’s driving safety and the location tracking accuracy. We propose an ABIwRC (Adaptive Beaconing Interval with Resource Coordination) method for a highway scenario. Each vehicle broadcasts beacon interval requests, including the intervals needed for both the vehicle’s driving safety and location tracking accuracy. The RSU(Road Side Unit) allocates resources for a vehicle’s beaconing according to the requests from all vehicles and the interference relationship between the vehicles in adjacent RSUs. We formulate a resource allocation problem for maximizing the sum utility, which measures the satisfaction of vehicles’requests. We then transform the optimization problem into a maximum weighted independent set problem, and propose an algorithm to solve this efficiently. Simulation results show that the proposed method outperforms the benchmark in terms of beacon reception ratio, vehicle driving safety, and location tracking accuracy.
Information security is an important issue in vehicular networks as the accuracy and integrity of information is a prerequisite to the satisfactory performance of virtually all vehicular network applications. We study the information security of a vehicular Ad hoc network whose message could be tampered by malicious vehicles. An analytical framework is developed to analyze the process of message dissemination in a vehicular network with malicious vehicles randomly distributed in the network. The probability that a destination vehicle at a fixed distance can receive the message correctly from the source vehicle is obtained. Simulations are conducted to validate the accuracy of the theoretical analysis. Our results demonstrate the impact of network topology and the distribution of malicious vehicles on the correct delivery of a message in vehicular Ad hoc networks, and provides insight on the design of security mechanisms to improve the security of message dissemination in vehicular networks.
With the evolution of conventional VANETs(Vehicle Ad-hoc Networks)into the IoV(Internet of Vehicles), vehicle-based spatial crowdsourcing has become a potential solution for crowdsourcing applications. In vehicular networks, a spatial-temporal task/question can be outsourced (i. e. , task/question relating to a particular location and in a specific time period) to some suitable smart vehicles (also known as workers) and then these workers can help solve the task/question. However, an inevitable barrier to the widespread deployment of spatial crowdsourcing applications in vehicular networks is the concern of privacy. Hence, We propose a novel privacy-friendly spatial crowdsourcing scheme. Unlike the existing schemes, the proposed scheme considers the privacy issue from a new perspective according that the spatial-temporal tasks can be linked and analyzed to break the location privacy of workers. Specifically, to address the challenge, three privacy requirements (i. e. anonymity, untraceability, and unlinkability) are defined and the proposed scheme combines an efficient anonymous technique with a new composite privacy metric to protect against attackers. Detailed privacy analyses show that the proposed scheme is privacy-friendly. In addition, performance evaluations via extensive simulations are also conducted, and the results demonstrate the efficiency and effectiveness of the proposed scheme.
Vehicular network communication technology is currently attracting a considerable amount of attention. We consider a scenario in which vehicular communication nodes share the same spectrum resources and generate interference with other nodes. Compared with traditional interference-avoiding vehicular communications, this paper aims to increase the number of accessed communication links under the premise of satisfying the required QoS. In our research, communication nodes have opportunities to select relay nodes to both help improve their data transmissions and reduce their transmit power in order to decrease interference with other links while still satisfying their QoS requirements. Based on these objectives, we propose an innovative interference management method that considers link selection, power adaption, and communication mode selection simultaneously to maximize the number of communication links with the lowest power cost. Compared with traditional link-selection and power-adaption interference management schemes, the proposed scheme improves QoS satisfaction with high energy efficiency. Simulation results demonstrate both the efficiency and the effectiveness of the proposed scheme.
Ubiquitous broadband Internet access is one of the major goals of the next generation of wireless communications. However, there are still some locations where this is difficult to achieve. This is the case on moving vehicles and, particularly, on trains. Among the possible solutions to this problem, RoF (Radio-over-Fiber) architectures have been proposed as low-latency, cost-effective candidates. Two elements are introduced to extend the RoF approach. First, the carrier frequency is raised into the W-band (75-110 GHz) to increase the available capacity. Second, a mechanical beam-steering solution based on a Stewart platform is adopted for the transmitter antenna to allow it to follow a moving receiver along a known path, thereby enhancing the coverage area. The performance of a system transmitting a 2. 5 Gbit/s non-return-to-zero signal generated by photonic up-conversion over a wireless link is evaluated in terms of real-time BER (Bit Error Rate) measurements. The receiver is situated in different positions, and the orientation of the transmitter is changed accordingly. Values below the forward error correction limit for 7% overhead are obtained over a range of 60 cm around a center point situated 2 m away from the transmitter.
Applications of VANETs (Vehicular Ad hoc Networks) have their own requirements and challenges in wireless communication technology. Although regarded as the first standard for VANETs, IEEE 802. 11p is still in the field-trial stage. Recently, LTE V2X(Long-Term Evolution Vehicular to X)appeared as a systematic V2X solution based on TD-LTE(Time Division Long-Term Evolution)4G. It is regarded as the most powerful competitor to 802. 11p. We conduct link level simulations of LTE V2X and DSRC (Dedicated Short-Range Communication)for several different types of scenarios. Simulation results show that LTE V2X can achieve the same BLER(Block Error Ratio)with a lower SNR(Signal Noise Ratio)than DSRC. A more reliable link can be guaranteed by LTE V2X, which can achieve the same BLER with lower receiving power than DSRC. The coverage area of LTE V2X is larger than that of DSRC.
With the rapid development of smart driving and communications technologies, an increasing number of vehicles are cooperating with each other to improve traffic efficiency and travel safety. This paper conducts a comprehensive survey of multi-vehicle cooperation from the aspects of control and communication. Firstly, three typical multi-vehicle cooperation scenarios are summarized. Communication issues relating to multi-vehicle cooperation are then introduced, including communication types, requirements, and potential solutions. To address the control requirements, a general resource allocation solution for multi-vehicle cooperation is formulated; specifically, two types of resource allocation scheme for intersection management are proposed. Finally, performance of the proposed schemes is evaluated and compared.
In order to transfer large files and provide high-quality services in the IoV(Internet of Vehicles), intelligent routing and scheduling are indispensable for fast transfers and efficient network utilization, particularly when multi-path routing is allowed in the wired-transfer. Thus, a network administrator must select a set of feasible paths over which the transfer can be conducted. We consider a TBTS(Time-constrained Big-file Transfer Scheduling) problem in this paper. We prove that TBTS problem is NP-hard and that the TBTS problem can be solved by addressing a corresponding maximum flow over time problem with multi-path routing technique. We then propose both a heuristic algorithm(TBTS-H)and an exact algorithm (TBTS-A) to solve the TBTS problem. Although both of the proposed approaches can solve the TBTS problem, the heuristic runs more efficiently by trading accuracy for delay, while the exact algorithm can achieve high accuracy for delay, at the cost of increased running-time. The corresponding simulation results illustrate this trade-off. Additionally, we conduct some comparisons between our proposed approaches and a traditional single-path routing scheme.
The spectrum scarcity of VANETs (Vehicular Ad hoc Networks) can be alleviated by spectrum sharing technology. We present a framework of CCR-VANETs (Cellular-based Cognitive-radio Vehicular Ad hoc Networks). In CCR-VANETs, cellular network performs as primary network while VANET shares the downlink spectrum of cellular network. We consider a scalable urban grid scenario in which vehicles detect available spectrum holes and opportunistically access them according to a carrier-sensing multiple-access protocol. To restrict vehicles’ interference to primary receivers, we set a square preservation region around each particular street block where an active base station is located. The number of street blocks in the preservation region is calculated with the practical assumption that vehicles only know the locations of primary transmitters. We analyze the aggregate interference power from primary and secondary networks, then derive the lower-bound of downlink capacity for the primary network and lower-bound of V2V (Vehicle-to-Vehicle) channel capacity for the secondary network respectively. The numerical results demonstrate the impacts of different network parameters on inter-networks interference level and network capacities.
