An efficient anonymous certificateless authentication and key agreement scheme for smart grids

With the vibrant development of the Internet, smart grids have been provided with a suitable environment to flourish. Smart meters record and transmit electricity consumption information and send it to gateways and service providers. Power suppliers process the data to evaluate and predict the frequency of electricity consumption by users, to save resources. However, the power consumption information contained in the data may reveal users’ identity, community address or the frequency at home. If malicious attackers get these messages, the residential safety will be greatly threatened. Therefore, data needs to be protected. Authentication and key agreement protocol is a promising solution, which first realizes mutual authentication between communication parties, and then establishes a session key between them to protect transmitted data. Recently, Chai et al. proposed an authentication scheme based on SM2 authentication key exchange (AKE) protocol. Unfortunately, after our analysis, it is difficult to achieve forward security as they stated. Specifically, if the long term key of the communicating smart meter is leaked, the adversary can recover the session keys established before. Further, we propose a provable secure certificateless authentication and key agreement scheme. The security of the proposed scheme is analyzed by provable security and BAN logic. Compared with the existing scheme, our proposed scheme can achieve a better balance from the security properties, communication cost, and computation cost three aspects.