Currently I am working on PRESENT block cipher implementation (Hardware) and I am unable to understand the role of round counter in key scheduling part of cipher.

Can some share some insight on round counter and its working?

  • 3
    $\begingroup$ Can you say more about what research you've already done with references, and be more specific about where you're stuck? $\endgroup$ – Squeamish Ossifrage Sep 13 '17 at 22:02
  • $\begingroup$ I would assume it has the same purpose as Rcon in the AES key schedule $\endgroup$ – Richie Frame Sep 14 '17 at 9:54

to prevent self-similarity of key scheduling

The importance of constant addition (not only present cipher) appears in preventing key schedule-based attacks such as slide attack ,related key attacks and other structural attacks such as: invariant subspace attack , and nonlinear invariant subspace attacks.

paragraph 5.4 Key schedule attacks in original Present Block cipher answers your questions.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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