V2G Networks Research Articles

Foud: Integrating Fog and Cloud for 5G-Enabled V2G Networks

V2G technology is considered a powerful approach enabling renewable energy sources to provide ancillary electrical services, and managing and monitoring power usage in the smart grid. However, owing to the inherent high mobility of EVs, flexible and timely on-demand response services against EV mobility in the V2G system must be provided. Promoted by the advantages of 5G communications, e.g., supporting various connectivity and faster transmission, fogs and clouds are enabled to provide realistic services, and fog computing and cloud computing assisted V2G systems in future 5G mobile networks are expected to be a new paradigm to create a new situation for V2G services. To this end, a fogbased and cloud-based hybrid computing model named "Foud" applied to V2G networks in 5G is proposed. The potential V2G network services provided by Foud are reviewed, and open issues and challenges for future work are also discussed with possible solutions.

Distributed Energy Management for Vehicle-to-Grid Networks

Making full use of V2G services, EVs with batteries may assist the smart grid in alleviating peaks of energy consumption. Aiming to develop a systematic understanding of the interplay between smart grid and EVs, an architecture for the V2G networks with the EV aggregator is designed to maintain the balance between energy suppliers (the grid side) and consumers (the EV side). We propose a combined control and communication approach considering distributed features and vehicle preferences in order to ensure efficient energy transfer. In our model, the integrated communication and control unit can achieve realtime and intelligent management with the logic controller and collected data. On the consumers' side, we theoretically analyze how to satisfy the charging constraints that we incorporate in the form of willingness to pay, and propose a distributed framework to coordinate the energy delivery behaviors for satisfying service demands. Moreover, illustrative results indicate that the proposed approach can yield higher revenue than the conventional pricing mechanism in V2G networks.

An Anonymous Authentication Scheme for Vehicle-to-Grid Networks

Vehicle to grid technology allows bidirectional energy exchange between electric vehicles and the power grid for achieving many known benefits. However, V2G networks suffer from certain security threats, such as EV’s privacy and authentication problem. In this paper, we propose an anonymous group authentication scheme for V2G communications. This scheme realizes dynamic joining and revocation of EVs, and greatly reduces the overhead of EV revocation. Through the theoretical analysis, this scheme can ensure identity privacy of EV user and security of data transmission in the process of charging and discharging.

IP2DM: integrated privacy-preserving data management architecture for smart grid V2G networks

IP²DM: integrated privacy-preserving data management architecture for smart grid V2G networks

Authentication Scheme for Flexible Charging and Discharging of Mobile Vehicles in the V2G Networks

Navigating security and privacy challenges is one of the crucial requirements in the vehicle-to-grid (V2G) network. Since electric vehicles (EVs) need to provide their private information to aggregators/servers when charging/discharging at different charging stations, privacy of the vehicle owners can be compromised if the information is misused, traced, or revealed. In a wide V2G network, where vehicles can move outside of their home network to visiting networks, security and privacy become even more challenging due to untrusted entities in the visiting networks. Although some privacy-preserving solutions were proposed in the literature to tackle this problem, they do not protect against well-known security attacks and generate a huge overhead. Therefore, we propose a mutual authentication scheme to preserve privacy of the EV's information from aggregators/servers in the home as well as distributed visiting V2G networks. Our scheme, based on a bilinear pairing technique with an accumulator performing batch verification, yields higher system efficiency, defeats various security attacks, and maintains untraceability, forward privacy, and identity anonymity. A performance analysis shows that our scheme, in comparison with the existing solutions, significantly generates lower communication and computation overheads in the home and centralized V2G networks, and comparable overheads in the distributed visiting V2G networks.

TPP: Traceable Privacy-Preserving Communication and Precise Reward for Vehicle-to-Grid Networks in Smart Grids

In vehicle-to-grid (V2G) networks, service providers are battery-powered vehicles, and the service consumer is the power grid. Security and privacy concerns are major obstacles for V2G networks to be extensively deployed. In 2011, Yang et al. proposed a very interesting privacy-preserving communication and precise reward architecture for V2G networks in smart grids. In this paper, we enhance Yang et al. ’s framework with the formal definitions of unforgeability and restrictiveness. Then, we propose a new traceable privacy-preserving communication and precise reward scheme with available cryptographic primitives. The proposed scheme is formally proven secure with well-established assumptions in the random oracle model. Thorough theoretical and experimental analyses demonstrate that our scheme is efficient and practical for secure V2G networks in smart grids.

An anonymous authentication scheme for plug-in electric vehicles joining to charging/discharging station in vehicle-to-Grid (V2G) networks

Incorporating electric vehicles into smart grid, vehicle-to-Grid (V2G) makes it feasible to charge for large-scale electric vehicles, and in turn support electric vehicles, as mobile and distributed storage units, to discharge to smart grid. In order to provide reliable and efficient services, the operator of V2G networks needs to monitor real-time status of every plug-in electric vehicle (PEV) and then evaluate current electricity storage capability. Anonymity, aggregation and dynamic management are three basic but crucial characteristics of which the services of V2G networks should be. However, few of existing authentication schemes for V2G networks could satisfy them simultaneously. In this paper, we propose a secure and efficient authentication scheme with privacy-preserving for V2G networks. The scheme makes the charging/discharging station authenticate PEVs anonymously and manage them dynamically. Moreover, the monitoring data collected by the charging/discharging station could be sent to a local aggregator (LAG) in batch mode. In particular, time overheads during verification stage are independent with the number of involved PEVs, and there is no need to update the membership certificate and key pair before PEV logs out.

PHEV Charging and Discharging Cooperation in V2G Networks: A Coalition Game Approach

Recently, plug-in hybrid electric vehicles (PHEVs) have attracted considerable attention as a sustainable transport system and also an essential component of the smart grid. With the rapid growth of PHEVs penetration, the charging and discharging of PHEVs will pose a significant impact on the residential electricity distribution network. For this reason, the management of PHEV charging and discharging has become one of the key issues in the research of PHEVs. In most existing work, PHEVs are supposed to operate individually for charging and discharging in the grid. However, we argue that, by leveraging the cooperation among PHEVs, the grid will efficiently stimulate PHEV users to charge in load valley and discharge in load peak. As a consequence, the electricity load is well balanced. Meanwhile, the PHEV users also achieve higher profit. The PHEV charging and discharging cooperation is a win-win strategy for both the grid and the PHEV users. We formulate and resolve the PHEV charging and discharging cooperation in the framework of coalition game. The simulation results indicate that the peak-valley difference in electricity load of the grid is significantly reduced. Besides, the PHEV users have better satisfaction in the vehicle battery status and the economic profit.

Role-Dependent Privacy Preservation for Secure V2G Networks in the Smart Grid

Vehicle-to-grid (V2G), involving both charging and discharging of battery vehicles (BVs), enhances the smart grid substantially to alleviate peaks in power consumption. In a V2G scenario, the communications between BVs and power grid may confront severe cyber security vulnerabilities. Traditionally, authentication mechanisms are solely designed for the BVs when they charge electricity as energy customers. In this paper, we first show that, when a BV interacts with the power grid, it may act in one of three roles: 1) energy demand (i.e., a customer); 2) energy storage; and 3) energy supply (i.e., a generator). In each role, we further demonstrate that the BV has dissimilar security and privacy concerns. Hence, the traditional approach that only considers BVs as energy customers is not universally applicable for the interactions in the smart grid. To address this new security challenge, we propose a role-dependent privacy preservation scheme (ROPS) to achieve secure interactions between a BV and power grid. In the ROPS, a set of interlinked subprotocols is proposed to incorporate different privacy considerations when a BV acts as a customer, storage, or a generator. We also outline both centralized and distributed discharging operations when a BV feeds energy back into the grid. Finally, security analysis is performed to indicate that the proposed ROPS owns required security and privacy properties and can be a highly potential security solution for V2G networks in the smart grid. The identified security challenge as well as the proposed ROPS scheme indicates that role-awareness is crucial for secure V2G networks.

Threshold-Based Privacy-Preserving Key Management Scheme for Vehicle-to-Grid Networks

The concept of vehicle-to-grid (V2G) is that electric vehicles (EVs) communicate with the smart grid to sell demand response services by delivering electricity into the grid. Due to the scale of the network, the speed of the vehicles, their geographic positions, and the very sporadic connectivity between them, V2G communications have the crucial requirements of fast session key establishment. In this paper, we propose a threshold-based privacy-preserving key management scheme for V2G networks, which utilizes the threshold-based secret sharing and symmetric key technique to protect the identities of the EV owners and to establish the shared session key between the aggregator and the vehicle. The proposed scheme can achieve the property of identity privacy, confidentiality of the communications, and known-key security.

Securing vehicle-to-grid communications in the smart grid

Using vehicle-to-grid (V2G) services, battery vehicles (BVs) may help the smart grid alleviate peaks in power consumption. However, wireless communications infrastructure between BVs and the smart grid also introduce severe and unprecedented security vulnerabilities. In this article, we discuss V2G network architectures and present state-of-the-art security, including different security challenges during V2G power and communications interactions. Then we report on our context-aware authentication solution for V2G communications in the smart grid. Finally, we describe several open issues for secure V2G networks.

Battery Status-aware Authentication Scheme for V2G Networks in Smart Grid

Vehicle-to-grid (V2G) is emerging as an attractive paradigm in smart grid, and provides power and information services by periodically collecting power status of battery vehicles (BVs). During a BV's interaction with power grid, it may be in one of the following states: charging, fully-charged (FC), and discharging. In this paper, we identify that there are unique security challenges in a BV's different battery states. Accordingly, we propose a battery status-aware authentication scheme (BASA) to address the issue for V2G networks. In BASA, 1) an aggregated-identifier is proposed during the charging-to-FC state transition to ensure that BVs can be authenticated without disclosing their real identities; 2) selective disclosure based challenge-response authentication is presented during the FC-to-discharging phase to realize anonymous data transmission; 3) an aggregated-status is reported during the discharging-to-charging transition in order to hide a BV's power level from an aggregator. In addition, we perform comprehensive security analysis, which shows that BASA achieves both privacy preservation and security protection during battery state transitions. The analysis also indicates that battery status awareness is crucial for BVs' secure operations for V2G networks in smart grid.

Cryptanalysis and Improvement of a Unique Batch Authentication Protocol for Vehicle-to-Grid Communications

The concept of vehicle-to-grid (V2G) is that electric vehicles (EVs) communicate with the smart grid to sell demand response services by delivering electricity into the grid. By letting EVs discharge during peak hours and charge during off-peak hours, V2G networks could bring numerous social and technical benefits to the smart grid. Due to the scale of the network, the speed of the vehicles, their geographic positions, and the very sporadic connectivity between them, V2G communications have the crucial requirements of fast authentication. In 2011, Guo et al. proposed a unique batch authentication protocol for V2G communications. There are three parties in V2G communications, including an aggregator, a smart grid control centre, and individual EVs. The proposed idea is that instead of verifying each packet for each vehicle, the aggregator verifies the received batch of packets with only one signature verification. They used DSA signature for the batch authentication and claimed their protocol is strong enough to defend against security attacks. In this paper, we investigate the security of Guo et al.’s protocol. More precisely, we show that any attackers can easily forge signatures satisfying the batch verification criterion without the knowledge of the signer’s private key. To remedy the security flaw of Guo et al.’s protocol, we proposed a simple and secure improvement of Guo et al.’s protocol. The key point of the improved protocol is that we make multiple signatures in order. The attacker or the dishonest signer cannot transpose these digital signatures such that the aggregator passes the validation of the batch verifying multiple digital signatures. Based on Guo et al.’s protocol, the security of our proposed protocol is the same as that of their protocol except that our improved protocol has no security flaw of their protocol. Therefore, the improved protocol is secure to detect forged multiple signatures.

Aggregated-Proofs Based Privacy-Preserving Authentication for V2G Networks in the Smart Grid

Vehicle-to-grid (V2G) as an essential network component of smart grid, provides services by periodically collecting the charging status of a battery vehicle (BV). A BV is normally associated with a default interest group (e.g., power grid operator). When the BV accesses its default charging or communication point, it works in the home mode. The BV may move around and temporarily access other aggregators, and then it works in the visiting mode. In this paper, we first identify that, for an aggregator, BVs have different security challenges when they work in different modes. Then, we propose an aggregated-proofs based privacy-preserving authentication scheme (AP3A) to achieve simultaneous identification and secure identification for different working mode BVs. In AP3A, BVs are differentiated into either home or visiting mode, and multiple BVs can be simultaneously authenticated by an aggregator to conserve communication resources. In addition, the aggregated pseudo-status variation is presented to realize that multiple BVs' power status can be collected as a whole without revealing any individual privacy. We perform comprehensive analysis on the proposed scheme, including attack analysis, security analysis, and performance analysis. It is shown that AP3A can resist major attacks for security protection and privacy preservation, and can be an efficient authentication approach for V2G networks.

$P^{2}$: Privacy-Preserving Communication and Precise Reward Architecture for V2G Networks in Smart Grid

Vehicle-to-grid (V2G) networks are important components of the smart grid (SG) for their capability of providing better ancillary services and facilitating the adoption of renewable resources. The operation of the V2G networks is based on continuously monitoring the status of individual battery vehicle (BV) as well as a carefully designed incentive scheme to attract sufficient participating BVs. However, the close monitoring tends to raise privacy concerns from the BV owners about identity and location information leakage, which have not been considered in previous works. In this paper, we make the first attempt to identify the privacy-preserving issues and propose a precise reward scheme in V2G networks, both of which are important towards bringing the concept of V2G network into practice. In V2G networks, it is the service providers (individual BVs) who need privacy protection rather than the service consumer (power grid). This unique characteristic renders privacy protection solutions proposed for conventional network systems not directly applicable. To protect privacy of BVs in V2G networks, we present , a secure communication architecture which achieves privacy-preserving for both BVs' monitoring and rewarding processes. Extensive performance analysis shows that only incurs moderate communication and computational overheads.