The Equivalence of Two Quadratic Based IBEs

George Teseleanu

Paper 2026/1092

The Equivalence of Two Quadratic Based IBEs

George Teseleanu

Abstract

In this short note, we show that two identity-based encryption schemes, introduced by Joye and Zhao et al., which appear different, are essentially the same scheme. The only difference between them is that one prioritizes speed (Zhao et al.), while the other prioritizes bandwidth (Joye). We also show how to speed-up Joye's scheme at the cost of adding at most one integer to the public key, thereby achieving a better encryption complexity, while having the same bandwidth requirements.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Published elsewhere. Minor revision. Secrypt 2026
Keywords: identity based encryption quadratic residues
Contact author(s): george teseleanu @ yahoo com
History: 2026-08-06: last of 2 revisions; 2026-05-29: received; See all versions
Short URL: https://ia.cr/2026/1092
License: CC BY-NC-SA

BibTeX

@misc{cryptoeprint:2026/1092,
      author = {George Teseleanu},
      title = {The Equivalence of Two Quadratic Based {IBEs}},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/1092},
      year = {2026},
      url = {https://eprint.iacr.org/2026/1092}
}