# Internet of Things for Modern Energy Systems: State-of-the-Art, Challenges, and Open Issues
## 2 Key Features in the Energy Internet
### Security and Privacy  
One of the main questions every system faces is that who is in charge of the system, and to what extent an authority can control the system, especially in modern energy systems with many independent players [59; 60]. Security is an inseparable part of IoT architecture because of its importance and effect on the whole system performance [59]. As energy systems become more complex, security concerns are raised. In other words, integration of IoT with energy systems makes the security issue more vulnerable; therefore, more attention must be paid to system security [60]. As an example, integration of wireless and wired communication network in energy systems increases accessibility to information and subsequently makes system security more vulnerable [61]. On the other hand, a key feature to implement the IoT in the energy system is trust. If system components, in this case, people, want to use a facility, it would be more appropriate if system asks for their permission in advance. In this manner, there would be less violation of users' privacy [62]. Moreover, in [63], users are involved in management of their security and privacy. This leads to a trusted privacy management system where both sides (consumers and service providers) have a degree of controllability over their privacy. As Big Data (BD) is available on an IoT platform, many service providers, like public and private health care companies, can access different types of information. In this manner, users' information can be shared with some third parties, which in turn raises issues about the privacy of the end-users. Generally, it is suggested that every accessibility to information is possible with the permission of end-users, unless the information will not be shared with service providers [64]. The privacy issue drives the problem into a more complex one, as adaptive service scenario should be designed. Figure 2: Establishing a communication link between end users and Evolved Node B (eNodeB). Generally, there are two types of information related to security of an IoT system. The first type of information is that people do not want to share it for the sake of their privacy, such as the position of their electric vehicle during a day. The second type of information is that end-users are worried about the security of their information, as they may suffer financial loss if specific third parties are informed about it, like their bank account or the monthly energy consumption. A solution for privacy issue of IoT systems for both cases, mentioned in [65], is to ask end-users to use their information for a specific purpose or to inform them that the information shall not be shared with any other third parties. What is obviously accepted here is that consumers feel more confident when they are asked for the accessibility of their information. Aside from this, a key feature to meet the end-users' and service providers' trust is to ensure that the system is secure. A great effort has been done in reviewing most parts of security of Cyber Physical Systems (CPS) such as threats, attacks, and controls in [66]. In [67], an encryption scheme is introduced to secure energy information from unauthorized manipulations. In this manner, energy systems are divided into four categories: appliance group, monitor group, central controller, and interface with users. Each level needs its own security scheme. To do so, data integrity, computational complexity, and needed memory size must be taken into account to have the best energy efficiency. More security is demanded when data is transferred among IoT components, including communication between IoT devices and the gateways, gateways and data store, data store and data access layer, and users and data access layer [68].