ディフィー・ヘルマン鍵共有
It was the need to synchronize the scramblers that suggested to James H. Ellis the idea for non-secret encryption, which ultimately led to the invention of both the RSA encryption algorithm and Diffie–Hellman key exchange well before either was reinvented publicly by Rivest, Shamir, and Adleman, or by Diffie and Hellman.