# Blockchain Technology Applied in IoV Demand Response Management: A Systematic Literature Review
## 4 Discussion
To balance load and supply, a large number of centralized generators and energy storage devices should be placed, resulting in a considerable CAPEX and operational expense OPEX. Another option is to investigate the rapid spread of DR, which may be used in smart cities to allow energy users to proactively change how and when they use (or create) energy based on the cost (or reward). Because IoV is a participatory data exchange and storage platform, the underlying information exchange system has to be safe, transparent and immutable in order to accomplish the desired objectives. In this regard, the use of blockchain as a system platform for addressing the IoV's demands was investigated. IoV applications enabled by blockchain are thought to offer a variety of desirable features, such as decentralization, security, transparency, immutability and automation, due to their decentralized and immutable nature. Even though the current studies have several similarities, there are still open research challenges that need to be further investigated. The identified challenges are described below among with some suggestions for further investigation. Research Challenges and Suggestions 1:  
* Research Challenge 1: EV information is exposed, resulting in privacy and security issues. * Suggestion 1: Blockchain infrastructure and identity management for secure information exchange in IoV. * Description: The existing charging coordination mechanisms suffer from their relation to a single entity (e.g., the charging coordinator), which can reveal private information about the owners of the EVs (e.g., patterns and drivers' profiles). Thus, the integration of blockchain in the IoV should guarantee the privacy of all participants and the security of the exchanged information. Research Challenges and Suggestions 2:  
* Research Challenge 2: Demand and response in IoV are affected by energy generation and consumption. * Suggestion 2: V2V/V2G Energy Trading considering EVs' Charging Scheduling addressing the Demand Response Problem. * Description: The widespread use of unpredictable dispersed RES and uncoordinated EVs creates problems for smart energy management. Current studies are investigating the optimization of the charging scheduling of EVs, although they do not consider the regional energy balance, leading to demand-response gaps and energy imbalances. Thus, emphasis should be given to the energy demand and response of the EVs in specific regions of a smart grid (e.g., considering social events and/or accidents). Research Challenges and Suggestions 3:  
* Research Challenge 3: EV charging profiling from an EV user perspective is not investigated. * Suggestion 3: EV profiling for optimal charging scheduling and DR balance. * Description: EV charging profiling from an EV user perspective is not sufficiently investigated. This means that each EV user should be aware of and declare its charging preferences and also to update this information in a continuous manner. In order to successfully control the charging/discharging schedule in comparison to IoV metrics and stability, a certain amount of smartness should be considered. Research Challenges and Suggestions 4:  
* Research Challenge 4: Due to a lack of incentives, EVs with excess energy are not encouraged to act as energy marketers. * Suggestion 4: Incentive provisioning through rewards and penalties. * Description: There is too little work conducted in the area of incentivization mechanisms. The majority of the studies do not consider any incentive mechanism to encourage EV drivers to participate in a blockchain-enabled DRM scheme. Therefore, it is necessary to provide an effective incentivization scheme that will give the appropriate rewards and/or penalties to the IoV participants and exploit the blockchain related activities.