Biometrics 2.0 for the Security of Smart Cities

In modern society, an increasing number of occasions need to effectively verify people′s identities. Biometrics is the most effective technology for personal authentication. Theoretical research on automated biometrics recognition mainly started in the 1960s and 1970s. In the following 50 years, the research and application of biometrics have achieved fruitful results. Approximately 2014–2015, with the successful applications of some emerging information technologies and tools, such as deep learning, cloud computing, big data, mobile communication, smartphones, location-based services, blockchain, new sensing technology, the Internet of Things and federated learning, biometric technology entered a new development phase. Therefore, taking 2014–2015 as the time boundary, the development of biometric technology can be divided into two phases. In addition, according to our knowledge and understanding of biometrics, we further divide the development of biometric technology into three phases, i.e., biometrics 1.0, 2.0 and 3.0. Biometrics 1.0 is the primary development phase, or the traditional development phase. Biometrics 2.0 is an explosive development phase due to the breakthroughs caused by some emerging information technologies. At present, we are in the development phase of biometrics 2.0. Biometrics 3.0 is the future development phase of biometrics. In the biometrics 3.0 phase, biometric technology will be fully mature and can meet the needs of various applications. Biometrics 1.0 is the initial phase of the development of biometric technology, while biometrics 2.0 is the advanced phase. In this paper, we provide a brief review of biometrics 1.0. Then, the concept of biometrics 2.0 is defined, and the architecture of biometrics 2.0 is presented. In particular, the application architecture of biometrics 2.0 in smart cities is proposed. The challenges and perspectives of biometrics 2.0 are also discussed.