English

If P \neq NP then Some Strongly Noninvertible Functions are Invertible

Computational Complexity 2016-08-15 v1

Abstract

Rabi, Rivest, and Sherman alter the standard notion of noninvertibility to a new notion they call strong noninvertibility, and show -- via explicit cryptographic protocols for secret-key agreement ([RS93,RS97] attribute this to Rivest and Sherman) and digital signatures [RS93,RS97] -- that strongly noninvertible functions would be very useful components in protocol design. Their definition of strong noninvertibility has a small twist (``respecting the argument given'') that is needed to ensure cryptographic usefulness. In this paper, we show that this small twist has a large, unexpected consequence: Unless P=NP, some strongly noninvertible functions are invertible.

Keywords

Cite

@article{arxiv.cs/0010011,
  title  = {If P \neq NP then Some Strongly Noninvertible Functions are Invertible},
  author = {Lane A. Hemaspaandra and Kari Pasanen and Jörg Rothe},
  journal= {arXiv preprint arXiv:cs/0010011},
  year   = {2016}
}

Comments

Extended and updated version of UR-CS-TR-00-737