# Internet of Things for Modern Energy Systems: State-of-the-Art, Challenges, and Open Issues
## 3 IoT Challenges in Energy Systems
### Standards  
IoT covers a large range of technologies and use cases that range from a single device to massive cross-platform deployments of embedded systems connecting in real-time while following different standards [105]. The mismatch among IoT devices using different standards and protocols is a major problem. Assume that some information needs to be sent from an Apple iPhone device to some other mobile devices via Bluetooth. This may not be possible as Apple devices can only be connected to Apple devices via Bluetooth. The very first step in standardization of IoT-based energy system is to define a system of systems with a common sense of understanding. In this manner, it is worth mentioning some of the organizations' definitions of IoT are as follows:  
* IEEE: The IoT is the integration of things, equipped with sensors, via the internet. * The European Telecommunications Standards Institute (ETSI): This institute does not provide a direct definition of the IoT. However, it brings a definition for M2M communication. M2M communications is a kind of communication among devices for which there is no need of human direct manipulations. * The International Telecommunication Union (ITU): the IoT is a ubiquitous network, which means that it is available anywhere, anytime, by anything and anyone. This definition does not answer specific questions like what is the range of availability of an IoT system, yet generally, it brings a great presentation of an IoT system. In addition, ITU Telecommunication Standardization Sector (ITU-T) mentioned the IoT system as an infrastructure for information society that connect physical and virtual things together. This definition includes all inanimate objects. Aside from the mentioned institutes, some companies provide definitions about the IoT. Some of them are mentioned as follows:  
* The Systems, Applications, and Products in Data Processing (SAP): The IoT is a world where physical things are defined in the information network, hence they can participate in business activities. * The CISCO: this company defines the Internet of everything as gathering people, data, and things in order to provide a network, which is capable of exchanging information into actions. * The Hewlett-Packard Company (HP): the IoT is a system, for which every object is defined on the internet. This means that human can manipulate and control objects from any place; and devices can communicate with each other without human interactions [106]. What is explicitly obvious from the comparison of IoT definitions provided by a non-profit institute and companies is that they all define the IoT in a same manner, yet companies try to provide a definition for which its benefit for the people is bold. In summary, the IoT is an infrastructure including sensors, communication system, data processing system, and objects that are connected via the Internet, in order to bring services and applications for people with minimum human intervention. Based on this definition, related standards should be addressed for communication systems, data processing, the Internet protocols, services, and applications. In case of communication systems, for example, IEEE 802.15.4-based (ZigBee) is one of the mostly adopted standards about low-rate wireless networks [107]. Based on this standard, data can be transferred at 800/900 MHz and 2.4 GHz. Other standards like IEEE 802.11p have also been developed for wireless communications. IEEE 802.11 is the standard about Wireless Local Area Networks (WLANs) in a vehicular environment. Communication bandwidth in the mentioned standard is 10 MHz and 5.9 GHz frequency band [108]. It is worth mentioning that technologies like LoRa and Sigfox present long range, low power consumption data transmission, and are used widely in IoT-driven systems [109; 110]. The range of frequency accepted by the aforementioned technologies is in 863-870 MHz [110]. Main advantages of LoRa and Sigfox technologies are their free-license availability.