Because of the significant advancements in information technology, patients can now receive real-time medical services over the Internet using the telecare medical information system \(\left( {{\mathcal{T}\mathcal{M}}I{\mathcal{S}}} \right)\) rather than visiting the hospital. Patients can gather their physiological data and upload it to the cloud using their mobile devices, a wireless body area network, and a cloud-based architecture. This enables medical professionals to give patients the best care possible at any time and wherever. It is possible for attackers to perform malicious actions on patient medical reports sent over open channels. Patient privacy and security during transmission and storage of their medical records on the cloud server are critical aspects of the \({\mathcal{T}\mathcal{M}}I{\mathcal{S}}\) . In recent years, scholar have introduced many privacy-preserving authentication systems to assure safe transmission and storage of patient medical reports in \({\mathcal{T}\mathcal{M}}I{\mathcal{S}}\) . However, these techniques are concerned about increased computing complexity and security weaknesses, which reduce their relevance for real-world applications. In order to address the security and performance concerns, we present a lightweight, privacy-preserving mutual authentication technique for cloud-assisted \({\mathcal{T}\mathcal{M}}I{\mathcal{S} }\) based on ECC. The proposed scheme significantly decreases computational cost while meeting all the security requirements of the \({\mathcal{T}\mathcal{M}}I{\mathcal{S}}\) domain. The random Oracle model \( \left( {{\mathcal{R}\mathcal{O}\mathcal{M}}} \right)\) and the ProVerif 1.93 tool are used for formal security analysis. Additionally, we present an informal security assessment of the proposed scheme, demonstrating that it is effective in defending against the most common cryptographic attacks. The Big Integer class of Java is used to implement and test the proposed scheme. We also carried out a comprehensive computational and communicational cost analysis through experiments, which clearly demonstrates that our proposed scheme produces more cost-effective results than other existing schemes in its category.
