# A Comprehensive Survey on the Societal Aspects of Smart Cities
## 3 Smart Cities' Technologies
### Standards/Open Standards  
Standards for smart cities define the requirements for the technologies and processes that everyone implementing them must abide by. In this way, a base level of quality is established, and different organizations can work in conjunction more easily. In this section, we will discuss the status of standards for smart cities. Each city faces its own unique set of challenges and has implemented solutions accordingly. Since many of these issues are common to many cities (e.g., traffic congestion, waste management, or sustainability), it is expected that solutions implemented by a city might be usable by other cities. However, since many of these solutions are often tailored to a particular city, they may not be easily transferable to other cities. This stems from the fact of how young the field of research for smart cities is, resulting in a constant stream of new ideas being created and tested. However, there is currently no consensus on a standard approach, and different cities may have varying priorities, even when addressing the same problem. For example, one city may prioritize solving their energy problem by updating their energy grid while another may focus on improving street lighting. This means that cities implement different applications to solve similar problems. For smart cities to become commonplace, it is necessary for the underlying technologies to transition from the realm of research to the world of market and industry. This requires the establishment of standards that the industry can apply. Standards enable different companies to construct different parts of a smart city and have those parts seamlessly interconnect without additional effort or expense. The International Organization for Standardization (ISO), an independent organization responsible for developing and publishing international standards in various technical and non-technical fields, has published numerous standards directly related to smart cities [194]. In addition to ISO, there are other organizations that develop and publish standards which are used internationally, such as the International Electrotechnical Commission (IEC), the Institute of Electrical and Electronic Engineers Standards Association (IEEE SA), or the International Telecommunication Union (ITU). Although the IEC and IEEE are different types of organization--the former being an international standards organization and the latter being a part of the Institute of Electrical and Electronic Engineers (IEEE), a North American professional's association--both deal with standards for electric, electronic, and related technologies. The ITU is the specialized agency of the United Nations (UN) for ICTs and works to facilitate international connectivity in communications networks, with one of their responsibilities being the developing of technical standards. As can be seen in Table 2 these organizations have published several standards for smart cities and they can be organized by their area of relevance: (i) organizational refers to standards that focus on establishing requirements, models, frameworks, and practices on how to implement and develop a smart city; (ii) architectures and interoperability refers to standards on how to implement the infrastructure of a smart city and how the various components operate with each other; (iii) data collection addresses how data are collected and treated to be free of errors; (iv) big data details how the large volumes of data produced by smart cities can be stored, analyzed, and visualized in an efficient manner; (v) artificial intelligence standards handle how ML and AI can be used in smart cities; (vi) security standards handle how to address the various security and privacy risks present in smart cities; (vii) metrics provide the tools to assess and quantify implemented smart city initiatives for review on their effectiveness; (viii) specifics present standards that are used in for distinct smart city applications that may not be addressed by other standards or require more specific details.