Understand why quantum computers threaten today's public key cryptography, learn the new NIST standards, and plan and run the migration before it is urgent.
Estimated time: 13–26 months · At about 10 hours a week.
Learning path
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Explain which cryptography quantum computers break and which they only weaken.
Explain the harvest-now-decrypt-later risk to a non-specialist.
Know the main algorithm families and their trade-offs.
Hands-on projects and labs
Write a one-page briefing on the quantum threat for your organisation.
List which of your systems hold data that must stay secret for more than ten years.
Done when you can…
Explain the quantum threat and the migration timelines clearly.
Identify the long-lived secrets in a sample organisation.
Beginner
Why quantum breaks today's crypto
Shor's algorithm would break RSA, Diffie-Hellman and elliptic curves. Symmetric crypto and hashes are weakened less and mostly need larger sizes. Know which is which.
Lattice, hash-based, code-based and others each trade off size, speed and maturity. Lattice schemes won the first standards; hash-based signatures are the conservative fallback.
Quantum key distribution and quantum random generators are often sold as the answer; they are not a migration. Post-quantum algorithms run on ordinary computers.
Explain ML-KEM, ML-DSA and SLH-DSA and where each fits.
Design and justify hybrid schemes.
Know current protocol and library support.
Measure performance impacts.
Hands-on projects and labs
Build a TLS connection with hybrid post-quantum key exchange using the Open Quantum Safe tools.
Sign and verify with ML-DSA and compare signature sizes with ECDSA.
Measure the handshake cost of post-quantum TLS against classical TLS.
Done when you can…
Demonstrate a working post-quantum key exchange and signature in a lab.
Explain the trade-offs of each standard to an engineering team.
Intermediate
ML-KEM (FIPS 203)
The standard post-quantum key encapsulation mechanism, from Kyber. Learn how it replaces Diffie-Hellman and RSA for key exchange, and its key and ciphertext sizes.
A stateless hash-based signature from SPHINCS+, with very conservative security but large signatures. Stateful schemes such as LMS and XMSS suit firmware signing.
Combine a classical and a post-quantum algorithm so security holds if either survives. Hybrid key exchange is already deployed in major browsers and servers.
Prioritise migration by data lifetime and exposure.
Engineer cryptographic agility into systems.
Manage vendor post-quantum readiness.
Hands-on projects and labs
Inventory the cryptography in a sample estate using scanning tools and manual review.
Migrate a lab service to hybrid post-quantum TLS without breaking clients.
Write post-quantum requirements for a procurement.
Done when you can…
Produce a cryptographic inventory and a prioritised migration plan.
Migrate a real service to post-quantum key exchange.
Advanced
Cryptographic inventory
Find every use of public key crypto: TLS endpoints, certificates, code signing, VPNs, tokens, hardware and third-party products. This is the hardest and most important step.
Start with long-lived secrets, root-of-trust signing and anything exposed to recording. Rank by data lifetime, exposure and how hard the system is to change.
Certificate authorities, chains and HSMs all need post-quantum support. Plan for larger certificates and for hybrid or composite options during transition.
A large enough quantum computer would break RSA and elliptic curve cryptography, which protect most of today's traffic, signatures and identities. Data captured now can be decrypted later, so the risk starts before the machine exists.
NIST has standardised new algorithms designed to resist quantum attacks. The work now is understanding them, building a cryptographic inventory, making systems agile, and migrating in a sensible order. It is mostly an engineering and programme challenge, not a maths one.
Why it matters
Governments and regulators have set migration timelines, and the harvest-now-decrypt-later threat is real for long-lived secrets. Organisations need people who understand the new standards and can run a multi-year migration across sprawling systems.
Typical job roles
Mid-levelSecurity engineer (PQC focus)Tests and integrates post-quantum algorithms.
SeniorCryptography engineerDesigns hybrid and post-quantum systems.
SeniorPQC migration leadRuns the inventory and migration programme.
LeadSecurity architectSets the quantum-readiness strategy.
NIST Cybersecurity Framework (CSF) 2.0A common way to describe and improve an organisation's security, organised as Govern, Identify, Protect, Detect, Respond and Recover.