The current 5G-AKA protocol faces significant security challenges, including the lack of Perfect Forward Secrecy and Post-Quantum (PQ) security. In particular, the absence of PQ protection makes current communications vulnerable to future quantum adversaries who may decrypt stored messages once large-scale quantum computers become available. To mitigate this risk, a transition to PQ security must be implemented as soon as possible. Two primary approaches exist for this transition: (1) symmetric key-based techniques, which require a secure channel for key distribution, leading to increased costs, and (2) modern PQ public-key primitives, which offer stronger security but come with high communication overhead. In this paper, we propose a solution that leverages PQ cryptographic primitives for confidentiality and privacy protection, while retaining classical public-key cryptography for authentication. This approach is viable because digital signatures must be secure today, even if they are compromised in the future. Moreover, our framework allows for a seamless transition to fully PQ-secure authentication when quantum threats become imminent. In addition, the framework also supports the zero-trust architecture in which no secure channel between Serving Network (SN) and Home Network (HN) is assumed. We have carefully analysed the security of the proposed protocol using both informal and formal (Real-Or-Random (ROR) logic and Scyther Validation tool) methods. We also compared its performance in terms of computation, communication, and storage, and found that it performs better than existing protocols.
The current 5G-AKA protocol faces significant security challenges, including the lack of Perfect Forward Secrecy and Post-Quantum (PQ) security. In particular, the absence of PQ protection makes current communications vulnerable to future quantum adversaries who may decrypt stored messages once large-scale quantum computers become available. To mitigate this risk, a transition to PQ security must be implemented as soon as possible. Two primary approaches exist for this transition: (1) symmetric key-based techniques, which require a secure channel for key distribution, leading to increased costs, and (2) modern PQ public-key primitives, which offer stronger security but come with high communication overhead. In this paper, we propose a solution that leverages PQ cryptographic primitives for confidentiality and privacy protection, while retaining classical public-key cryptography for authentication. This approach is viable because digital signatures must be secure today, even if they are compromised in the future. Moreover, our framework allows for a seamless transition to fully PQ-secure authentication when quantum threats become imminent. In addition, the framework also supports the zero-trust architecture in which no secure channel between Serving Network (SN) and Home Network (HN) is assumed. We have carefully analysed the security of the proposed protocol using both informal and formal (Real-Or-Random (ROR) logic and Scyther Validation tool) methods. We also compared its performance in terms of computation, communication, and storage, and found that it performs better than existing protocols.
Advancements in 5G are largely driven by its adoption across a variety of applications, including smart homes, smart healthcare, autonomous vehicles, transportation, and Industry 5.0. However, this widespread usage raises significant security and privacy concerns, particularly regarding authentication. To secure 5G communications, 3GPP has standardised the 5G-Authentication and Key Agreement (5G-AKA) protocol. Despite this, state-of-the-art research has revealed that 5G-AKA suffers from several vulnerabilities. In response, numerous alternative authentication schemes have been proposed. Nevertheless, many of these protocols continue to be susceptible to classical security threats, such as malicious serving network (SN) attacks, ephemeral secret leakage, traceability, anonymity violations, and, most critically, a lack of Perfect Forward Secrecy (PFS). Additionally, recent advancements in quantum computing pose a substantial risk to the security of 5G-AKA and its variants, rendering them insecure in the post-quantum era. Although a few post-quantum cryptography-based protocols have been introduced, studies show that they are either computationally expensive or still vulnerable to quantum attacks. In order to tackle these challenges, we propose two versions of a novel authentication protocol that not only provide comprehensive security guarantees but are also computationally efficient. Version 1 utilises a hybrid cryptographic approach (AES + KEM) and achieves the lowest computational cost—even lower than Version 2, which relies solely on KEM. Both versions offer the same level of security, but Version 1 is significantly more efficient in terms of resource usage. We have validated our proposed protocols using the Real-Or-Random (ROR) model and the Scyther tool. Furthermore, we evaluated their performance against existing protocols under both known and unknown attack scenarios. The results show that our protocols incur lower computational, communication, and energy overhead, as well as strong resilience against unknown attacks, outperforming several existing authentication schemes. Furthermore, we implement a testbed to demonstrate the real-time applicability of both proposed versions.
5G communication enables digital innovation by integrating a wide range of services, making security, especially primary authentication, critically important. To secure 5G communication, the 3GPP has designed the 5G Authentication and Key Agreement (5G-AKA) protocol. However, current trends show a growing interest in post-quantum security, and 5G-AKA is not resistant to quantum-era threats due to several classical vulnerabilities. To address these limitations, various enhanced versions of 5G-AKA have been proposed, claiming to provide security against attacks that exploit its weaknesses. However, state-of-the-art research reveals that many of these versions remain susceptible to classical threats, such as attacks from malicious serving networks (SNs), ephemeral secret leakage (ESL) attacks, and fail to provide perfect forward secrecy. Additionally, they are not secure against quantum attacks. In response to these challenges, we propose a Post-Quantum Secure, Lattice-Based 5G-AKA Protocol that is resistant to malicious serving networks and ensures perfect forward secrecy. Our proposed protocol is built on lattice-based cryptography, making it one of the first 5G-AKA variants designed with post-quantum security in mind. We validate the security of our protocol using formal verification techniques, including the Real-Or-Random (ROR) model and the Scyther tool. Furthermore, we perform a comparative analysis with existing protocols to highlight the improvements. Finally, we implement our protocol in a testbed environment to demonstrate its practical feasibility for real-time 5G applications.
5G serves as a catalyst for transformative digital innovation by enabling convergence with various services in our daily lives. The success of this paradigm shift undeniably hinges on robust security measures, with primary authentication— securing access to the 5G network—being paramount. Two protocols, 5G Authentication and Key Agreement (5G-AKA) and the Extensible Authentication Protocol for Authentication and Key Agreement Prime (EAP-AKA’), have been standardized for this purpose, with the former designed for 3rd Generation Partnership Project (3GPP) devices and the latter for non-3GPP devices. However, recent studies have exposed vulnerabilities in the 5G-AKA protocol, rendering it susceptible to security breaches, including linkability attacks. Furthermore, the advent of quantum computing poses significant quantum threats, underscoring the urgent need for the adoption of quantum-resistant cryptographic mechanisms. Although post-quantum cryptography (PQC) is being standardized, the lack of real-world deployment limits its proven robustness. In contrast, conventional cryptographic schemes have demonstrated reliability over decades of practical application. To address this gap, the Internet Engineering Task Force (IETF) has initiated the standardization of hybrid PQC algorithms (HPQC), combining classical and quantum-resistant techniques. Consequently, ensuring forward secrecy and resilience to quantum threats in the 5G-AKA protocol is critical. To address these security challenges, we propose the 5G-AKA-HPQC protocol. Our protocol is designed to maintain compatibility with existing standards while enhancing security by combining keys negotiated via the Elliptic Curve Integrated Encryption Scheme (ECIES) with those derived from a PQC-Key Encapsulation Mechanism (KEM). To rigorously and comprehensively validate the security of 5G-AKA-HPQC, we employ formal verification tools such as SVO Logic and ProVerif. The results confirm the protocol’s security and correctness. Furthermore, performance evaluations highlight the computational and communication overheads inherent to 5G-AKA-HPQC. With only average of 56.5 millisecond(+112.32%) on a total authentication time, proposed protocol provides its advantages. Also, on a environment of multiple UE registration, compared to single UE registration, the difference of increased rate of average authentication time is only 0.01%. The negligible difference 0.01% indicates that the addition of PQC does not lead to increased overhead in multi-UE registration environments, demonstrating its scalability and practical feasibility. In conclusion, our research provides significant insights into the design of secure, quantum-safe authentication protocols and lays the groundwork for the future standardization of secure authentication and key agreement protocols for mobile telecommunications.
The evolution of 6G networks necessitates robust authentication and key agreement (AKA) protocols to counter emerging security challenges, particularly the threat posed by quantum computing. Existing 5G-AKA protocols remain vulnerable to user tracking, replay attacks, and false base station impersonation, while Elliptic Curve Cryptography (ECC) and RSA-based key exchanges face imminent obsolescence due to quantum attacks. This study examines the vulnerabilities of 5G-AKA and explores hybrid post-quantum cryptography (PQC) as a transitional security solution for 6G networks. We evaluate NIST-standardized PQC algorithms, focusing on their computational overhead, key size efficiency, and adaptability to heterogeneous network environments, including IoT and ultra-low latency applications. A comparative analysis of hybrid cryptographic schemes demonstrates that lattice-based (Kyber, Dilithium), hash-based (SPHINCS+), and code-based (BIKE, Classic McEliece) PQC techniques provide varying trade-offs between security, efficiency, and deployment feasibility. Furthermore, we propose a quantum-resistant 6G-AKA framework, integrating hybrid PQC, AI-driven trust mechanisms, and decentralized authentication to ensure scalability and interoperability. Experimental benchmarks highlight potential performance constraints, including latency in PQC-based key exchange and resource limitations in edge computing. Addressing these challenges requires the optimization of lightweight PQC implementations, formal security validation, and global standardization efforts. Our findings provide a roadmap for the secure transition to 6G authentication protocols, ensuring resilience against both classical and quantum threats.
The authentication process in fifth-generation networks between the user equipment and the network relies on secure communication protocols, with the 5G authentication and key agreement (5G-AKA) being a prominent one. However, this protocol still has shortcomings, as identified in the 3rd Generation Partnership Project (3GPP)release, which poses vulnerabilities. Notably, a primary concern is the insufficient protection of user privacy. This deficiency allows attackers to potentially exploit weaknesses in encryption, signing, and update mechanisms, leading to the tracking of a user's identity, location, and activities. Furthermore, the5G-AKA protocol is vulnerable to man-in-the-middle attacks, in which malicious actors can assume the identity of service providers or networks, leading to the interruption of communication between users and servers. Additionally, the protocol lacks robustness in guaranteeing mutual authentication, enabling attackers to forge authentication messages and manipulate user data. In this paper, we propose a key generation method based on the concept of post-quantum cryptography to provide robust resistance to attacks. Furthermore, we propose a key exchange method that authenticates the user's equipment and home network through the application of Kyber, where both parties possess pre-established static public keys. The proposal provides identity protection, non-traceability, mutual authentication, and confidentiality. We implement this protocol to test 5G-AKA's vulnerabilities and analyse its effectiveness against specific attacks. The experiment used Minnet simulation and Ryu controllers to implement 5G-AKA with standard-specified characteristics.
Vehicle-to-Everything (V2X) communication is a critical enabler of autonomous driving, supporting real-time information exchange among vehicles, roadside infrastructure, pedestrians, and cloud services. However, the security of current V2X systems largely relies on classical cryptographic mechanisms, which are expected to become vulnerable in the presence of large-scale quantum computers. Given the long operational lifespan and stringent safety requirements of autonomous vehicular networks, the transition toward quantum-resistant authentication and key management mechanisms has become increasingly important. This paper presents a comprehensive survey of post-quantum Authentication and Key Agreement (AKA) protocols for secure V2X communications. The survey systematically reviews V2X communication architectures, security and privacy requirements, existing authentication frameworks, and emerging post-quantum cryptographic approaches. Representative AKA schemes and NIST-standardized post-quantum algorithms are comparatively analyzed in terms of security strength, computational complexity, communication overhead, storage requirements, scalability, and deployment suitability for resource-constrained vehicular environments. The survey further examines practical implementation challenges, including latency constraints, bandwidth limitations, signature size expansion, memory consumption, and hardware resource requirements. The analysis reveals that achieving quantum-resistant security in V2X networks requires balancing strong cryptographic protection with the stringent performance demands of safety-critical vehicular applications. While recent post-quantum approaches offer promising security guarantees against quantum adversaries, their practical deployment remains constrained by computational and communication overhead. Finally, this survey identifies key research gaps and outlines future directions for the development of lightweight, scalable, and quantum-resilient AKA frameworks capable of supporting next-generation autonomous transportation systems. The findings provide researchers and practitioners with a structured understanding of the opportunities, limitations, and challenges associated with securing future V2X communications in the quantum era.