In the VCC, the mobility of nodes is very high and topology changes in the network frequently so appeared issues and challenges facing the VCC such as message confidentiality, trust management, securing vehicular communication, authentication, secure location information, the safety of messages, and the interoperability of different clouds. All these challenges can be discussed and concentrate on the issues correlated with ITS applications like security, traffic management, navigation systems, and congestion detection [7, 8, 9, 10, 11 and 12].
Threats for Vehicular Cloud Computing: all VCC components: vehicles, passengers, messages, wireless communication, and architectures need security against attackers. In vehicles, attackers attempting to access application unit and enter malware in it, while wireless communication considered between the vehicles or RSUs via V2V and V2R communication the best environment for the attackers, because it contains some vulnerabilities.
The wireless communication threats classified into:
- Denial of Service (DoS): it blocks communication by using reject any members to forward important messages to other vehicles or the cloud.
- Data tempering (modification): in this type, the attacker objects the messages when the routes to other vehicles or RSUs and after that can modify and alter it.
- Jamming: DoS attack to make jamming in the channel for wireless communication which carries the messages.
There are also several threats like repudiation, information disclosure, and sybil attack. To provide secure vehicular cloud computing, communication takes considering requirements for security like authentication, integrity, and confidentiality.
Authentication, Privacy, and Liability: In VCC, the communication depends on the integrity of messages and authentication of the users. To increased authenticate between RSUs and vehicles in the vehicular networks, the vehicles used aliases to deception the attackers for not track their communication and activities.
Also, exchange information between the vehicles requires being privacy and trust. The privacy is one of the most important challenges in VCC. Many researchers are working to find methods and solutions used to protect the privacy of the vehicles in a vehicular network. The passengers and drivers have controlled exchange information and determine, what the information open on networks, and what the information keeps private and can’t broadcast on the networks.
Service Delay and Location: Because to the topology in the network changes quickly, the time and location play an important role on data packets sent by applications for vehicular networking. In VCC, the most applications depend on the information on the current location of a vehicle such as collision, congestion avoidance, and traffic status.
The vehicular networks use devices like GPS, filtering, inter-cell position, and radar to check the location information. Many researchers proposed several methods to check the location information. These methods can classify into three types: active location, active location and general location [7].
In vehicular cloud computing, the delay can impact on price for service. So, the passengers and drivers are interested about service delay, because the increase of service delay leads up to increase the price for service.
Confidentiality, Integrity, and Trust for Messages: At VCC, messages split into four types: the first one using to send alerts or warning messages called short message, second known as media message, utilize when the vehicle needs services from other cloud or vehicles, priority message is third one employed to end the warning messages, the last one acknowledge message after delivery of messages send these to confirm access.
Most applications for a vehicular network focused verification and trust to provide a secure communication. Confidentiality is an important issue; all messages in the network can’t read by an unauthorized user, but after encrypting the messages and allowing only access to authorized users.
Therefore, the RSU registers all vehicles and users that enter the domain to increase confidentiality by using secure and encrypted communication. Furthermore, to safeguard the networks from security threats such as denial of service, forgery and jamming attack, must verify the integrity for receiving messages.
Securing Vehicular Communication: In the environment of a vehicular cloud, from the important providing secure communications to avoid attackers and reduce security holes like traffic tampering, privacy violations, forging messages, and preventing communication by utilizing cryptographic algorithms [13,14].
The big problem facing the cryptographic algorithm is key management, so found a method for the solution this problem. The Vehicular Public Key Infrastructure (VPKI) is one of the methods key management to guarantee confidentiality and integrity of the message in vehicular networks.
Opportunities and Future For VCC
The vehicular cloud computing plays a major role in people’s lives due to traffic management and providing safety, security, trust, and comfort of passengers and drivers, so considered very rich environment for researchers. It considers the basis for improving and developing intelligent transportation systems. However, the development and improvement process still constrained by several factors such as challenges and issues for VCC.
Several applications and services appeared in the last days result from exploiting the resources by the vehicular cloud. Future of VCC in the next day’s benefits of underutilized resource and exploits it to the maximum extent such as to benefits, capacities of storage and computation which owned by modern vehicles, and time which wasted in the parking. So, some companies are thinking to rent resource from the parking to carry out some application or task.
In [15], the authors present a new method, known Virtual Cord Protocol (VCP), depends on the benefit from parked vehicles to create a cloud for storing information and to provide network communication between the moving vehicles and the vehicle storing the requested data. The inter-domain routing techniques used to enable dynamic cloud services and to achieve the communication between the moving vehicles and cloud.
He, et al proposed a new architecture for IoT-based vehicular data clouds, by integrating several devices, cloud computing, and IOT to Share resources and exchange information among the passengers, vehicles, and roadside infrastructure [16]. The [16] study and face two vehicular data cloud services: the first one is intelligent parking cloud service and the second is the mining vehicular maintenance data service. Although finding several challenges this method provides enormous opportunities for technology in the vehicle industry.
Wan, Jiafu, et al proposes a context-aware architecture with mobile cloud support and two crucial service components, namely cloud-assisted Context-aware Vehicular Cyer-physical systems (CVCs). This paper studies context-aware dynamic parking service as a case study to improve QoS and the performance of CVCs. Addition, discuss the challenges and find potential solutions [17]. It will consider this attractive field for researchers in the near future.
To benefit from sensors such as map, radar, and lidar the authors proposed a new method to detect the vehicles on the way or parked on the roadside to provide the best motion, the easiest method to pass the parked vehicle, and assuring safety for drivers and passengers [18]. Additionally, assist drivers to make the decision to choose the smooth and safe path to avoid harassing from other vehicles.
The traffic accidents and traffic flow issues are major challenges for VCC, maybe occur when the vehicles parked on the way illegally. So, the authors presented the new system to monitor traffic and detect traffic flow to avoid accidents by using cumulative dual foreground differences [19]. The results appeared that the method is efficient and can be considered as part of the intelligent traffic monitoring system, but possibly generate false results when producing a noisy foreground image.
The nature VCC has open communication medium, fast topology changes, and dynamic. Thus, one of the key challenges is exchange information due to nature VCC can be fake and lead to sharing false information between drivers and passengers.
Sharma, M. K., et al presented a new method by using Elliptic Curve Cryptography (ECC) to provide security for communication to guarantee authentication, integrity, confidentiality, and privacy between sender and receiver [20]. The ECC has several advantages to against various attacks like spoofing attack, replay attack.
Huang, Cheng, et al presented new method, Privacy-Preserving Trust-Based Verifiable Vehicular Cloud Computing scheme (PTVC), to improve safety for traffic and offering services to passengers and drivers [21]. The mechanism PTVC system merges between the best advantages of VCC, techniques of verifying, and requirements of privacy, to select the trustworthy vehicle among the vehicles to create a vehicular cloud. The PTVC scheme proves is effective, secure and robust against several attacks
