MQ Signatures for PKI

Alan Szepieniec; Ward Beullens; Bart Preneel

Paper 2017/327

MQ Signatures for PKI

Alan Szepieniec, Ward Beullens, and Bart Preneel

Abstract

It is well known that multivariate quadratic (MQ) digital signature schemes have small signatures but huge public keys. However, in some settings, such as public key infrastructure (PKI), both variables are important. This paper explains how to transform any MQ signature scheme into one with a much smaller public key at the cost of a larger signature. The transformation aims to reduce the combined size of the public key and signature and this metric is improved significantly. The security of our transformation reduces to that of the underlying MQ signature scheme in the random oracle model. It is possible to decrease signature sizes even further but then its security is related to the conjectured hardness of a new problem, the Approximate MQ Problem (AMQ).

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. PQCRYPTO 2017
Keywords: multivariate quadratic public key infrastructure signature random oracle post-quantum hard problem
Contact author(s): alan szepieniec @ esat kuleuven be
History: 2017-04-17: received
Short URL: https://ia.cr/2017/327
License: CC BY

BibTeX

@misc{cryptoeprint:2017/327,
      author = {Alan Szepieniec and Ward Beullens and Bart Preneel},
      title = {{MQ} Signatures for {PKI}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2017/327},
      year = {2017},
      url = {https://eprint.iacr.org/2017/327}
}