What are documented early field uses of digital signature?

The oldest I found is reported by Charles H. Bennett, Gilles Brassard, Seth Breidbart, Stephen Wiesner's Quantum Cryptography, or Unforgeable Subway Tokens (in proceedings of Crypto 1982). They cite Gina B. Kolata's New Codes Coming into Use (in Popular Science, May 1980) as the source of the following. The relevant portion of both articles happen to be readable for free from the publisher's linked websites.

One of the first places public-key cryptography was applied is at the Zero Power Plutonium Reactor in Idaho Falls, Idaho. (Access) is controlled by personalized access cards containing information on their bearers hand. The novelty about this scheme is that it includes a digitalized signature based on a trap-door one-way function.

Is there an earlier documented field use of digital signature? Or/and another source for this one, ideally with details like the type of signature? The 1982 article suggests RSA, but that can't be deduced from the 1980 article, so either BBBW had a source they did not cite, or they guessed. If it was RSA, I think the system must have used signature with message recovery, as I see no other credible way to fit biometric data and a signature on a standard magnetic track of the times, with a useful capacity of barely 560 bit.


1 Answer 1


Interesting question. According to Simmons, this is indeed the first documented use of not only signatures, but public-key cryptography in general.

And you can see the Sandia report of this system, the "Secure stand alone positive personnel identity verification system", here. The report hints at the public keys being around 200 digits.

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    $\begingroup$ Great! These sources are much more detailed. They attest existence in March 1979, confirm RSA and hint on key size. The Simmons article mentions a then planned, more detailed paper: Gustavus Simmons, A system for verifying user identity and authorization at the Point-of Sale or Access, Cryptologia, 8:1, 1-21 (1984), available (with registration $\&$ for a sizable fee) $\overline\oplus$ legally, with (poorly scanned ) pictures. I accept the answer but this should not discourage others, if an earlier system or more sources are located. $\endgroup$
    – fgrieu
    Aug 17, 2021 at 13:57

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