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Vladimir
Vladimir

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CRYSTALS-Dilithium: Explained Simply for Beginners

KelVPN is a decentralized VPN.
Traditional digital signatures — like those used in banking cards — can be broken by a quantum computer.
CRYSTALS-Dilithium is a signature that a quantum computer can’t break.

What is Dilithium?

It’s a post-quantum digital signature.

In simple terms:
You send a message.
You attach a “digital fingerprint” — your signature.
The recipient checks: the signature is valid → you are authentic.
Dilithium makes this possible in a way that even a super-powerful quantum computer can’t forge it.

Where did it come from?

In 2016, the U.S. NIST launched a global competition: find signatures resistant to quantum attacks.
After 7 years of testing, analysis, and cryptographic attacks,
in 2022 the winner was announced — CRYSTALS-Dilithium.
In 2024, it became an official U.S. standard (FIPS 204).

How does it work? (Without math)

Imagine a huge lattice of points in multidimensional space.
Your signature is a short path through this lattice.
Forging a signature means finding the same short path.
A classical computer would take billions of years.
A quantum one? Still impossible — the problem is too complex.

The foundation is lattice-based cryptography.
It’s not magic — it’s geometry in thousands of dimensions.

Comparison with Traditional Signatures
Signature Quantum-safe? Size Speed
Ed25519 ❌ No 64 bytes ★★★★★
Dilithium ✅ Yes ~3 KB ★★★

Is it slower? Yes — but it works on smartphones and will still work 20 years from now.

How it’s used in KelVPN

When a node starts, it generates a Dilithium key.
It signs every connection.
Other nodes verify the signature — if valid, they allow it into the network.
Keys are stored in a distributed DHT network.
No central certificates, no single point of failure.

Why Dilithium?

Simple: Easy to implement.

Fast: Verification takes only fractions of a millisecond.

Reliable: Zero successful attacks in 7 years of testing.

Open: Code reviewed by thousands of developers worldwide.

Bottom Line

CRYSTALS-Dilithium is insurance against the future.
Today’s quantum computers can’t yet break digital signatures —
but in 10 years, they might.

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