- Person
- Adi Shamir
- Lived
- b. 1952
- Field
- Cryptography
- From
- Israeli
The story
Adi Shamir, born in Tel Aviv in 1952, is best known as the S in RSA, the encryption system he invented with Ron Rivest and Leonard Adleman at MIT in 1977. Two years later he published a short paper titled How to Share a Secret, which solved a different but equally practical problem: how to protect a secret that is too important to trust to any one person.
Imagine a bank’s master key, the key that signs a country’s secure websites, or the key that controls a large store of digital money. If one person holds it, that person can steal it, lose it or be coerced into giving it up. If several people each hold a full copy, the risk multiplies. Shamir’s idea uses a piece of school mathematics: two points define a line, three points define a curve called a parabola, and so on. The secret is hidden in a curve, and each participant receives one point on it. Any agreed number of participants, say three out of five, can combine their points to rebuild the curve and recover the secret. Crucially, anyone holding fewer points learns absolutely nothing about it.
This threshold scheme gives organisations exactly the protection they need. No single insider can act alone, yet the secret survives if some holders are unavailable or their shares are lost. The Wolf Foundation, awarding Shamir its 2024 prize in mathematics, described how his secret-sharing method turns secrets into sets of random numbers that must be combined in a specific way to reconstruct the original, forming the basis for secure computations.
According to the standard references, Shamir’s secret sharing is used most often to secure encryption keys. It protects the unseal keys of widely used key-management software such as HashiCorp Vault, the recovery keys of password managers and encrypted email services, and the master secrets of cryptocurrency wallets, for which a published standard, SLIP-0039, is based on it. It also underlies a whole field of research on secure multiparty computation, in which several parties compute together without revealing their private data.
Why it matters
Shamir’s secret sharing helps keep the master keys behind encrypted systems, password managers and digital wallets safe from theft, loss and rogue insiders.
About Adi Shamir
Israeli cryptographer, the S in RSA, the encryption method that protects online banking, shopping and private messages, and inventor of secret sharing. Turing Award 2002.
Sources
- Adi Shamir Wikipedia
- Adi Shamir, Wolf Prize Laureate in Mathematics 2024 Wolf Foundation
- Shamir’s secret sharing Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.