Lightweight and authentic symmetric session key cryptosystem for client–server mobile communication

Over the last decade, millions of 4G and 5G-enabled mobile devices have become part of the Internet. Almost, all the applications have been shifted to smartphones. A person connects his smartphone to several other devices or remote servers for exchanging sensitive data. In this sense, security threats in terms of authentication, data confidentiality, and data integrity are increasing day by day for mobile devices. The asymmetric key cryptosystem is considered more secure, but it is heavyweight for smart devices on the basis of computation and communication costs. The symmetric key cryptosystem is considered lightweight for smart devices in terms of computation and communication overheads, but it is vulnerable to several attacks such as MITM attacks. Several symmetric key security systems have been proposed for smart devices but adopt complex mathematical procedures. Therefore, existing symmetric key security systems increase the computation and communication overheads. In this paper, we propose a lightweight and authentic symmetric key cryptosystem for resource-constrained mobile client–server environments. Our proposed cryptosystem consists of a lightweight symmetric session key exchange algorithm, mutual authentication service, and data confidentiality service, respectively. Moreover, we prove the robustness of our proposed cryptosystem with the help of informal and formal security analysis through the AVISPA tool. In addition, performance evaluation and comparisons with existing security systems show that our proposed cryptosystem is efficient, lightweight, secure, and most suitable for mobile computing.