Confidential Computing is the protection of data in use by performing computation in a hardware-based, attested Trusted Execution Environment. However, even without specific hardware features, one can still protect computation to some extent using software solutions. Confidential Containers (CoCo) play a crucial role in providing confidential computing without specific hardware. Confidential Computing protects data in use. In contrast, data at rest and data in transit are only secured by means of traditional classical encryption algorithms such as Rivest-Shamir-Adleman (RSA) or Elliptic Curve Diffie-Hellman (ECDH). These algorithms face a significant threat from the advent of quantum computers, a threat known as the Quantum Threat. National Institute of Standards and Technology (NIST) has been leading efforts to standardize Post-Quantum Cryptography (PQC) algorithms such as — standardized quantum-resistant algorithms — CRYSTALS-Kyber and Dilithium that remain secure against quantum threats. These standardized PQC algorithms are built on mathematical problems believed to be hard for both classical and quantum computers, to protect our data against quantum attacks that powerful quantum computers could launch. This study presents an integration of confidential computing with PQC to secure data/computation in all stages of data —data in use, data at rest, and data in transit — even from quantum threats. Furthermore, the paper delivers a comparison of confidential computing with PQC to other traditional methods, such as Fully Homomorphic Encryption, and others. The study’s results demonstrate significantly lower overhead when using CC with PQC compared to FHE in experimental data payloads. It clearly stated that CC with PQC is a better feasible option than other traditional data in use methods.
5G saw the introduction of an encrypted user identifier, the Subscriber Concealed Identifier (SUCI), to provide confidentiality of the subscriber's whereabouts and identities. The SUCI protects the new generation of cellular networks against tracking devices, so-called IMSI-catchers, which have undermined users' confidentiality ever since the inception of cellular networks. However, the potential advent of large-scale quantum computers in the near future threatens to compromise the confidentiality provided by the SUCI yet again. The security of the public-key cryptography that underpins the SUCI relies on the hardness of the discrete logarithm problem. Using Shor's algorithm, a quantum adversary could break the SUCI's cryptography and once more gain the capability to track and identify users. Advancements in quantum computing are unpredictable, and a breakthrough might be only a decade away. Given the slow nature of standards and their implementation, it is thus necessary to already integrate now quantum-resistant cryptography into the current and also next-generation (6G) cellular networks. To contribute to this development, we propose a post-quantum secure scheme for the SUCI calculation, \textttKEMSUCI. To this end, we first analyze the weak points in the current SUCI calculation scheme when considering quantum attacks. We then describe an alternative SUCI calculation scheme based on post-quantum secure key-encapsulation mechanisms (KEMs). Our proposed scheme can use any of the KEMs submitted to the NIST call for standardization of post-quantum secure cryptography (PQC) schemes. For the usage in \textttKEMSUCI, the KEM should provide efficient execution on a SIM card and induce little network communication overhead. We evaluate all of the NIST PQC finalists under these aspects and identify Kyber and Saber as the best fit. Instantiated with these KEMs, \textttKEMSUCI can be integrated into 5G and 6G. Compared to the existing SUPI protection schemes, \textttKEMSUCI exhibits faster execution speed and only little communication overhead.
Recent developments in quantum computing have shed light on the shortcomings of the conventional public cryptosystem. Even while Shor's algorithm cannot yet be implemented on quantum computers, it indicates that asymmetric key encryption will not be practicable or secure in the near future. The National Institute of Standards and Technology (NIST) has started looking for a post-quantum encryption algorithm that is resistant to the development of future quantum computers as a response to this security concern. The current focus is on standardizing asymmetric cryptography that should be impenetrable by a quantum computer. This has become increasingly important in recent years. Currently, the process of standardizing asymmetric cryptography is coming very close to being finished. This study evaluated the performance of two post-quantum cryptography (PQC) algorithms, both of which were selected as NIST fourth-round finalists. The research assessed the key generation, encapsulation, and decapsulation operations, providing insights into their efficiency and suitability for real-world applications. Further research and standardization efforts are required to enable secure and efficient post-quantum encryption. When selecting appropriate post-quantum encryption algorithms for specific applications, factors such as security levels, performance requirements, key sizes, and platform compatibility should be taken into account. This paper provides helpful insight for post-quantum cryptography researchers and practitioners, assisting in the decision-making process for selecting appropriate algorithms to protect confidential data in the age of quantum computing.