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.
What it built on 2
What it led to 3
Related measurements
The dashed line marks when it first worked.
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