I have a question for my information security lab, which I am not able to find online. As the title says, is Diffie Hellman key exchange based on a one-way or a trapdoor function?

In case of RSA I would say it is based on a trapdoor function, since it is hard to factorize the modulo, if you don't know p and q.

Is Diffie Hellman also based on a trapdoor function, since it is hard to reverse the discrete logarithm, if you don't know the secret key?


1 Answer 1


No, the mathematical problem that is used for Diffie-Hellman is the Diffie-Hellman problem or DHP which is different from the trapdoor function that is behind RSA.

One way functions are for instance cryptographically secure hash functions.

  • $\begingroup$ Let me know if you need a mnemonic for that :P $\endgroup$
    – Maarten Bodewes
    Commented Jan 21, 2018 at 15:28
  • $\begingroup$ Oh okey, sounds good thanks :) Whats your mnemonic? :P $\endgroup$
    – 0x00
    Commented Jan 21, 2018 at 16:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.