Abstract

The development of efficient, cross-domain mobile application cryptographic environments requires seamless, secure authentication protocols. Traditional schemes remain bound to homogeneous settings, which significantly limit their applicability in the real world since clients and servers may operate on different cryptosystems. This paper presents a new secure user authentication protocol designed for heterogeneous mobile environments, where clients utilize identity-based cryptography (IBC) and servers employ certificateless cryptography (CLC). Our protocol supports mutual authentication, session key exchange, user anonymity, and protection from replay, impersonation, and man-in-the-middle attacks. A thorough security analysis reveals that, even in varying scenarios with enhanced key-compromised adversary capabilities, the proposed user authentication protocol remains robust against multiple threats. Additionally, performance evaluation indicates that mobile devices at the lower end of the resource spectrum benefit from the reduced computational and communication overhead achieved by our protocol, surpassing the improvements of previously established protocols. This work provides flexible, scalable, and efficient authentication solutions for next-generation mobile networks and services.