Classic McEliece

Code-based KEM descended from Robert McEliece's 1978 cryptosystem — the oldest unbroken public-key design in existence.

Core Principles & Analysis

• Forty-seven years of cryptanalysis have only nudged its parameters — the core design has never fallen.
• Its public keys run from a quarter megabyte to over a full megabyte, which kept it out of NIST's picks.
• Remains under consideration for ISO standardization and is favored where bandwidth is cheap and paranoia justified.

Specifications & Metrics

• FAMILY: Code-based (binary Goppa)
• STATUS: Unbroken since 1978
• PUBLIC KEY: 0.26–1.3 MB
• YEAR: 1978