Quantum-Safe Key Exchange Without the Complexity
In today’s hyperconnected world, so many interactions – including the authentication of human and non-human identities – rely on secure cryptographic keys. But with cyberattacks on the increase and quantum computing on the horizon, the cryptography that underpins these exchanges is under threat.
Post-quantum cryptography is a top priority for cybersecurity leaders. 70% of organizations are assessing or deploying quantum-safe measures, but only 15% are genuinely ready, according to Capgemini.
Symmetrikey is Cavero Quantum’s answer. It’s a new approach to key exchange and authentication that’s fast, flexible, and designed for a quantum-safe future. In this blog, we’re explaining how our technology works in simple terms – and showing you where you can find more details about how Symmetrikey works.
The Problem: Today’s Keys Are Easy to Break Tomorrow
In order to break traditional key exchange methods like RSA and ECDH, one would have to solve mathematical problems such as the discrete logarithm problem, or factoring an integer which is the product of two large prime numbers. Whilst such problems are hard for classical computers to solve, they are trivial for quantum computers. That means that encrypted messages sent today could be harvested and decrypted later, once a cryptographically relevant quantum computer is available to the attacker – which could be by as early as 2030, according to many estimates. These sorts of attacks, known as ‘hack now, decrypt later’ (HNDL) attacks, are on the rise. They are part of the reason that many governments are mandating migration to PQC solutions, with the NCSC in the UK mandating that critical systems are protected by PQC by 2028.
Obviously, HNDL attacks put data at risk, but the ability to crack encryption keys that will come with Q-Day also puts many authentication protocols at risk. Any authentication protocol relying on key exchange – such as public key infrastructure – is vulnerable to compromise, giving attackers the ability to impersonate trusted devices and individuals and cause catastrophic damage.
Existing solutions have drawbacks
Current quantum-safe alternatives to classical encryption include algorithms that deploy mathematical problems that are harder for quantum computers to solve, known as Post-Quantum Cryptography (PQC), and a completely different method of key exchange that relies on the properties of quantum physics, known as Quantum Key Distribution (QKD). Both have their merits but are often resource-intensive and complex to integrate. QKD in particular is unsuitable for long-distance applications due to being hardware-based, making it vulnerable to attacks on physical infrastructure.
The Solution: Meet Symmetrikey
Symmetrikey – first envisioned at the University of Leeds in 2011 – is a quantum-safe key exchange protocol that enables the creation of faster PQC solutions that function in constrained environments.
Symmetrikey uses Ring Learning With Errors (RLWE), a variant of the better-known problem Learning With Errors (LWE), to enable two parties to generate identical secret keys independently, by sharing summaries of their data that reveal nothing useful to an attacker. Despite years of research, no computational shortcuts using either classical or quantum computing have been found for LWE or RLWE, making it a quantum-safe problem.
Uniquely, Symmetrikey also includes a correlation filtering process inspired by QKD to generate mutual secret information. This process is far faster than other PQC algorithms, including ML-KEM, and in early benchmarking tests Symmetrikey has been shown to be nearly twice as fast as ML-KEM.
Why Symmetrikey Matters
Symmetrikey is designed for real-world performance, and fills a gap in the current market: lightweight yet quantum-safe key exchange. It’s compact enough to work in IoT devices, scalable enough for enterprise, and easier to integrate into existing security products and services than KEM-based PQC solutions.
Symmetrikey is also designed to work with Authentikey, the world’s first Continuous Trust Verification Protocol from Cavero Quantum. Authentikey uses the principles of zero trust and decentralisation to provide an alternative to PKI and similar authentication infrastructures that is more secure, lightweight, and provides both one-way and mutual authentication.
Key benefits
- Drop-in replacement for ECDH
- Software-only implementation
- Resistant to phishing, spoofing, and man-in-the-middle attacks
- Enables passwordless authentication and certificate-free infrastructure
Symmetrikey use cases
From telecoms and fintech to critical infrastructure and enterprise login systems, Symmetrikey supports:
- Secure quantum-safe messaging services
- Post-quantum VPNs
- Zero-trust enterprise frameworks
- Passwordless authentication
- IoT and other non-human identity authentication
Symmetrikey can play a role in defence and national security, to secure sensitive communications, limit threats, and safeguard mission-critical operations with quantum-safe encryption. In government services, to increase trust in government data and services with quantum-safe authentication and key exchange. Or for IoT and industrial devices, by securing diverse ecosystems, and protecting resource-constrained devices with low-latency, quantum-safe encryption.
Ready to Dive Deeper?
Symmetrikey is backed by rigorous maths, peer-reviewed cryptographic foundations, and real-world test cases. It is resistant to classical and quantum attacks, and demonstrates improved performance compared to other quantum-safe key exchange methods. It is computationally lightweight, enabling a broad range of practical use cases. And it’s not based on KEM framework, making it a straightforward drop-in replacement for ECDH.
Cavero Quantum is looking for partners interested in using our products to build the next generation of security products.
Download the whitepaper now and learn how Cavero Quantum is building a safer future for digital trust.