Bhed Bahadur Bista

Towards Secure Vehicular Clouds

The past decade has witnessed a growing interest in vehicular networking and its panoply of potential applications among vehicles. Olariu and his co-workers [1, 2, 3] have put forth the vision of a new type of cloud, Vehicular Cloud Computing (VCC). It is clear that the VCC concept raise exceptional security and privacy challenges. It is also clear that if the VCC concept is to see a wide adoption and to have a significant societal impact, security and privacy issues need to be addressed. In this paper we are interested to analyze the security challenges and potential privacy threats in VCC. We address some major design issues that will affect the future implementation of VCC and provide a set of security and privacy-protecting protocols. To the best of our knowledge, this is the first paper that deals with security problems in VCC. But we state that few VCC security issues are fundamentally new. Many of the security challenges have received attentions in related fields such as cloud computing and VANETs. On the other hand, we address relatively unique security challenges resulted by features of VCC, e.g. the challenges of authentication of high-mobility vehicles and the complexity of trust relationships among multi-players caused by intermittent short-range communication.

Securing Vehicular Ad-hoc Networks Against Malicious Drivers: A Probabilistic Approach

Future development of Intelligent Transportation Systems (ITS) depends on Vehicular Ad-hoc Networks (VANETs) in which communications will help to improve traffic safety and efficiency through exchanging information among vehicles. As each vehicle cannot be a source of all messages in VANET, most communications depend on the information received from other vehicles. To protect VANET from malicious action, each vehicle must be able to evaluate, decide and react locally on information received from other vehicles. Message verification is more challenging in VANETs since the security and privacy of the participating vehicles, in general, and of the drivers and passengers specifically is of major concern. Each vehicle needs to verify the accuracy of the message and needs to verify that the received message is from a legitimate vehicle. In this paper, we propose a new algorithm to secure vehicular communication with the help of trust measured for the given period using a probabilistic approach. The proposed algorithm secures VANETs against the untrustworthy drivers. The proposed algorithm is illustrated through numerical results obtained from simulations.

Provisioning Vehicular Ad Hoc Networks with Quality of Service

The vehicular wireless ad hoc network (VANET), a specialized wireless sensor network, is booming to provide safety and comfort for passengers. Special features of VANET, such as high mobility nodes and large scale node population, make the Quality of Service (QoS) task extremely challenging. To provide Quality of Service (QoS) to traffic safety and entertainment applications in VANET, we propose a routing protocol which improves QoS of VANET in terms of delay, response time and throughput. The proposed scheme disseminates packets among the links which has longer expiration time calculated by using relative velocity vectors. The optimal routing path and a backup routing path are selected by balancing stability, cost and delay. Besides, the proposed scheme gracefully switches to a new optimal routing path before the current routing path is broken. Simulation results indicate that the proposed protocol improves the bandwidth, routing duration, and response time.

An Efficient ZHLS Routing Protocol for Mobile Ad Hoc Networks

In this paper, in order to reduce communication overhead in mobile ad hoc networks, we present a zone-based hierarchical link state routing protocol with gateway flooding (ZHLS-GF) in which a new flooding scheme, called gateway flooding is proposed. ZHLS-GF is based on ZHLS, a zone-based hierarchical link state routing protocol. ZHLS is a hierarchical routing protocol for mobile ad hoc networks in which a network is divided into non-overlapping zones. All network nodes in ZHLS construct two routing tables, an intrazone routing table and an inter-zone routing table, by flooding NodeLSPs within the zone and ZoneLSPs throughout the network. However, this incurs a large communication overhead in the network. Our proposed flooding scheme floods ZoneLSPs only to the gateway nodes of zones thus reduces the communication overhead significantly. Furthermore in ZHLS-GF, only the gateway nodes store ZoneLSPs and construct interzone routing tables therefore the total storage capacity required in the network is less than ZHLS

Cloud-assisted GPS-driven dynamic spectrum access in cognitive radio vehicular networks for transportation cyber physical systems

Transportation Cyber Physical Systems (CPS) are expected to rely on robust wireless communication networks for real-time feedback for controlling these systems. The IEEE 802.11p based Dedicated Short Range Communication (DSRC) standard has been proposed for vehicular communications that has 7 channels. However, these channels could be easily congested resulting in delay and unreliable communications when vehicle density is high. In this paper, we present a cloud-assisted global positioning system (GPS)-driven dynamic spectrum access framework for transportation CPS. To provide reliable communications, we assume that each vehicle is equipped with two transceivers: one transceiver (always connected to the internet using e.g., 4G link) queries spectrum database and/or can serve as a GPS through an application (app), and the other transceiver/radio switches channels and adapts to suitable transmit parameters for vehicular communications to avoid any harmful interference to primary users (PUs). Each vehicle calculates the best route to its destination using GPS and finds the set of idle channels along the route. Furthermore, each vehicle periodically checks the spectrum database throughout the route to get most updated spectrum opportunities. We present performance evaluation of the proposed approach with the help numerical results obtained from simulations.

Vehicle-to-Vehicle Connectivity and Communication Framework for Vehicular Ad-Hoc Networks

Vehicle-to-Vehicle (V2V) communication in Vehicular Ad hoc Networks (VANETs) is one of the key ingredients in the Intelligent Transportation System (ITS) where vehicles receive relevant traffic information using wireless communications from their peers. Forwarding traffic information to drivers can assist with the tasks of avoiding traffic accidents and related congestion. In this paper, we investigate the effect of association time (a.k.a. connection setup time), relative speed of vehicles, transmission range and message/data size in short range based V2V communications. The analysis is illustrated with the numerical results obtained from simulations.

A Testbed Using USRP(TM) and LabView(R) for Dynamic Spectrum Access in Cognitive Radio Networks

Dynamic spectrum access is regarded as a backbone for cognitive radio networks where unlicensed secondary users (SUs) access spectrum opportunistically which is licensed to licensed primary users (PUs). SUs are required to identify the idle bands and use them dynamically without creating any harmful interference to PUs. In dynamic spectrum access for peer-to-peer based communications, SU transmitter and its intended SU receiver must use common channel to communicate. Note that the fixed common control channel could not be viable in case of jamming attacks and wideband regime. Thus in this paper, we present a test bed using Universal Software Radio Peripheral (NI USRP) devices. We use Lab View® and MATLAB® scripting extensions to program NI USRP devices for peer-to-peer communications. Once SU transmitter and receiver pair knows idle channels, they use one of the best idle channels to communicate. We study sequential channel scanning and quorum based rendezvous methods without using any common control channels. These two schemes are compared in terms of their performance for finding suitable channel. Test bed is developed to test these schemes. Numerical results are presented obtained from test bed.

General Active Position Detectors Protect VANET Security

Vehicle position is one of the most valuable pieces of information in a Vehicular Ad-hoc Network (VANET). The main contribution of this work is a novel approach to enhancing position security in VANETs. We propose a general active detection architecture including two components: eye-devices and ear-devices. Eye-devices include radar, infrared, camera, etc. Ear-device is the wireless transceiver. We achieve local security by enlisting the help of several on-board eye-devices to detect neighboring vehicles and to confirm their announced position coordinates heard by ear-device. We apply cosine similarity to these data to reach an agreed-location. Our solution is predicated on the widely accepted assumption that the vast majorities of vehicles are honest and behave responsively.

CoR-VANETs: Game Theoretic Approach for Channel and Rate Selection in Cognitive Radio VANETs

Vehicular network for intelligent transportation systems is emerging concept to improve transportation security, reliability, and management. Vehicular networks are expected to utilize wide range of wireless networks and services that enables vehicular users to enjoy all kinds of services on the road. The highly dynamically changing topology because of high mobility of vehicular nodes is the main challenges in formulating efficient method for switching channel and data rate for vehicular users. This paper presents a novel game theoretic approach to achieve higher throughput for vehicular users by changing wireless networks/channels and data rate in heterogeneous wireless networks. The performance of the proposed scheme is illustrated with the help of simulation results.

Location management in PCN by movement prediction of the mobile host

The mobile hosts mobility profile, in a personal communication network (PCN) environment, is modeled. It is argued that, for a majority of mobile hosts (MHs) for most of the time, the movement profile repeats on a day-to-day basis. The next movement strongly depends on the present location and the time of the day. In this paper, such a pattern for every individual MHs is learned. The model is not static and re-learning is initiated as the behavior of the mobile host changes. Thus the model assumes that the past patterns will repeat in future and a past causal relationship (i.e., next state depends on previous state) continue into the future. A copy of the model is uploaded at the home location register (HLR). This facilitates the system to predict to a high degree of accuracy the location of a MH. During the course of learning, as the model gets perfected, the frequency of updates decreases as well as the probability of success in paging improves. The model is continuously verified locally and re-learning is initiated when a shift in mobility pattern is detected. The validity of the proposed model was verified through simulations.