Discussion related to cado-nfs

[Pierrick Gaudry <pierrick.gaudry@loria.fr>]

Hi Sylvia,

Small ells are not allowed (hum... this should be added somewhere in the
README).

There is a theoretical reason for that: the Schirokauher maps are
computed in the standard way, that forbids the case where ell is involved
in the factorization of one of the relations. Therefore ell smaller than
the large prime bound is very likely to fail.

There exists a workaround to make this work even for small ell, but it is
not implemented (and will probably never be, because for small ell,
Pollard Rho is much, much faster than NFS).

Regards,
Pierrick


On Tue, Sep 01, 2015 at 03:41:46AM +0000, Chiang Pek Yin Sylvia wrote:
> Hi Pierrick,
> 
> We set gorder = small prime. The program exits on failure rc=1. 
> 
> Can CADO handle small ells?
> 
> With best regards,
> Sylvia
> 
> 
> -----Original Message-----
> From: Pierrick Gaudry [mailto:pierrick.gaudry@loria.fr] 
> Sent: Tuesday, 25 August 2015 5:10 PM
> To: Chiang Pek Yin Sylvia
> Cc: cado-nfs-discuss@lists.gforge.inria.fr
> Subject: Re: [Cado-nfs-discuss] NFS
> 
> Hi,
> 
> The p180 DL computation was done some time ago; the code has evolved since 
> then, in particular the code for the descent. Therefore, the parameters and 
> the hint file won't work anymore, and it would require some work to adapt 
> them, so we probably won't do it.
> 
> However, our plan is to provide everything (complete parameters and hint
> file) so that 512-bit DLP is completely automatic, with the hope that users 
> will be able to adjust them for other sizes.
> 
> This is a short-term goal, but don't expect this to be done in the next few 
> days.
> 
> Regards,
> Pierrick
> 
> On Mon, Aug 24, 2015 at 05:46:06AM +0000, Chiang Pek Yin Sylvia wrote:
> > Hello there,
> > 
> > Am looking at the CADO-NFS-DLP code.
> > 
> > Am wondering how the task.descend variables are being set up for p180. 
> > What should be the hint file.
> > 
> > Also, for p180, how many cores should we be using and how should we be 
> > distributing the cores in threading.
> > 
> > 
> > Thank you.
> > 
> > With best regards,
> > Sylvia
> 
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