On Thu, 22 Apr 2010, Zooko O'Whielacronx wrote:

On Wed, Apr 21, 2010 at 5:29 PM, Samuel Neves <sne...@dei.uc.pt> wrote
(on the cryptography@metzdowd.com list):
[2] http://www.cs.umd.edu/~jkatz/papers/dh-sigs-full.pdf

As one of the authors of the above paper, I have an obvious interest in this thread. =)

Later I discovered this paper [2] which appears to be an improvement
on that one in terms of performance (see Table 1 in [2]) while still
having a tight reduction to the Computational Diffie-Hellman (CDH)
problem. Strangely, this paper [2] doesn't appear to have been
published anywhere except as an eprint on eprint.iacr.org. I wonder
why not. Is there something wrong with it?

While I don't know of any attack, the proof of security does not appear to be correct.

On the other hand, there is one published scheme that gives a slight improvement to our paper (it has fewer on-line computations): it is a paper by Chevallier-Mames in Crypto 2005 titled "An Efficient CDH-Based Signature Scheme with a Tight Security Reduction".

The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com

Reply via email to