Stone to Silicon

Communication · 1976

Public-key cryptography

Two strangers can agree on a secret key over a public line.

Whitfield Diffie and Martin Hellman published their key exchange in 1976, and Rivest, Shamir and Adleman published RSA in 1977. Public keys made secure online banking, shopping, software updates and encrypted messaging possible without prior shared secrets.

See it in the living treeWikipedia

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 2

What it led to 3

Related measurements

The dashed line marks when it first worked.

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