From 2G to 6G: A comprehensive survey on the evolution and enhancement of AKA protocols for next-generation wireless networks

Authentication and Key Agreement (AKA) protocols are essential for secure communication in mobile networks, evolving from basic 2G mechanisms to advanced 5G systems. This survey reviews the development of AKA protocols, including single-user, group-based, aggregated, and PUF-based variants. We assess security challenges such as replay attacks, signaling overload, and authentication latency. The paper also explores how emerging technologies-AI, edge computing, blockchain, and post-quantum cryptography-support future-proof authentication. Consideration is given to application contexts like smart cities, industrial IoT, and disaster recovery. The study aims to guide optimized AKA design as networks transition toward 6G and ultra-dense, low-latency environments.