[RC5] RSA Secret-Key Challenge Termination

Open Phugu openphugu at gmail.com
Mon May 21 20:21:12 EDT 2007

On 5/21/07, Joseph Kaye <jkaye at isd.net> wrote:
> Jim C. Nasby wrote:
> > On Mon, May 21, 2007 at 08:53:35AM -0400, Greg Lobring wrote:
> >
> >> Personally I don't foresee myself continuing to crunch RC5-72 keys with the
> >> discontinuation of the challenge by RSA. In fact, I've already disabled the
> >> RC5-72 project on all my clients, they are doing only OGR work now. As it
> >> stands with yesterday's stats, it could be well over 1,000 years before
> >> RC5-72 is done. Even with progressing technology, I don't see that
> >> diminishing too much in my lifetime. I've put over 1,630 days (over 4 years)
> >> into the project, and seeing it at only 0.415% complete is a little
> >> depressing!
> >>
> >
> >
> > Personally, I think it would be a shame to officially close RC5-72
> > without at least taking these new cores for a spin.
> >
> Absolutely! Even if only so that the developers of the core could see
> the fruits of their labor, and see "what could have been". :)  Another
> question - would we be able to confirm if the key was found, or can only
> the RSA confirm this?

Once the key is found, anyone can decrypt the ciphertext with the key
and if the plaintext starts with ``The unknown message is:'', we have found
the key. RSA's role is only to verify that we have found the key and give us
the prize money.

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