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Isogeny-Based Key Exchange (CSIDH)

Interactive 3D CSIDH simulator: watch Alice and Bob each walk a commutative isogeny graph between supersingular elliptic curves with a secret key, exchange public curves, and converge on the same shared secret — post-quantum key exchange without exponentiation.

Cryptography3DAdvanced60 FPS📱 Mobile-adapted

Post-quantum cryptography needs a replacement for Diffie–Hellman that doesn't rely on the discrete-log or factoring problems Shor's algorithm breaks. CSIDH (Commutative Supersingular Isogeny Diffie–Hellman) gets there by walking a graph of elliptic curves connected by small-prime isogenies instead of multiplying group elements. This simulator renders that graph in 3D: Alice and Bob each pick a secret vector of small integers, walk from a shared base curve E0 to their own public curve, exchange those public curves, and then each applies their own secret walk to the curve they received. Because the underlying class-group action is commutative, both walks land on the exact same shared curve — the live vectors, step counters, and the converging gold marker confirm the match in real time.

⚙ Under the hood

Walk a commutative isogeny graph between supersingular elliptic curves the way CSIDH does: Alice and Bob each apply a secret sequence of small-prime isogenies to a base curve, exchange public curves, and because the class-group action is abelian, both converge on the same shared curve.

cryptographypost-quantumisogenykey-exchangeelliptic-curvecsidh

3D · Three.js / WebGL renderer · 60 FPS target · runs fully client-side, no install