Supposing I wanted to send a one-time pad to a friend. What would be a good way to do that, supposing that it could be intercepted? At first blush, encrypting it would seem safe, because the encryption would seem impossible to crack, given that what it encodes is random (result of unsuccessful decryption is not obviously indistinguishable from successful deception). Yet perhaps there is still a risk is if the encrypted one time pad and a message encoded with it were intercepted.

  • $\begingroup$ What is your motivation for sending a one-time pad to a friend vs. something like an AES key? If the answer is "protection against computationally-unbounded adversaries", sending it over a network can't work (especially since such an adversary could man-in-the-middle you). $\endgroup$
    – Mark
    May 10 '20 at 7:06

The strength of the scheme cannot be higher than its weakest element. Using OTP can give an impression of unbreakable strength, but actually the whole strength is the same as the strength of the encryption method used to share OTP keystream (AES?). Thus, the usage of OTP in such a scheme gives not more security than using normal encryption.

To your question How to share... ? For instance, you could deliver the OTP keystream to your friend in person, or your friend picks it up in person.


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