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Posts by jasonp

1) Message boards : Questions/Problems/Bugs : Open source? (Message 1759)
Posted 2 Apr 2017 by jasonp
Post:
I should clarify: The 14e and 15e sieve applications use the lasieve4 source in the link I posted previously. The 16e sieve is a completely separate codebase with a link posted here. This is the code that the BOINC client distributes.

For Msieve, anyone who volunteers to run postprocessing is responsible for their own copy of the Msieve application. In practice version 1.52 has been available for a long time, and v1.53 was released a few months ago. I would expect most postprocessing volunteers run the latest and greatest.
2) Message boards : Questions/Problems/Bugs : Open source? (Message 1758)
Posted 1 Apr 2017 by jasonp
Post:
There are two codebases involved here: we use the sieving tools from GGNFS and the Msieve code for finishing off each factorization. Neither have had serious updates in a while. The GGNFS sieving tools are very good at their job and contain a ton of assembly language for various CPUs, but they are also very difficult to understand and modify with confidence. Msieve is not an application that the BOINC project distributes, finishing each factorization does not run very well in parallel and is not amenable to using BOINC resources. I am the Msieve maintainer and welcome some help, but I've been at this a long time and making the postprocessing faster is not easy.

So if you don't mind a steep learning curve, optimizing the sieving tools is the way to go. The 16e sieving source is here, though the BOINC modifications are not included (but easy).
3) Message boards : NFS Discussion : Could this project be used to expose Diffie-Hellman groups that are booby trapped? (Message 1719)
Posted 19 Oct 2016 by jasonp
Post:
The booby trap requires a discrete logarithm computation and not a big factorization. The only software that's publicly available and has any hope of performing a really big discrete log job is CADO-NFS, which NFS@Home does not use.
4) Message boards : Questions/Problems/Bugs : Prime Factor (Message 1409)
Posted 23 Jun 2014 by jasonp
Post:
512 bits is not large enough to require NFS@Home; a single machine can do the job in a few core-weeks.
5) Message boards : Questions/Problems/Bugs : Prime Factor (Message 1403)
Posted 22 Jun 2014 by jasonp
Post:
If you mean the numbers from the old RSA contest, actually there are many numbers up to 2048 bits that have not been factored. It's true there hasn't been an RSA-type key larger than RSA768 (publicly) factored since 2010.
6) Message boards : Questions/Problems/Bugs : Will using a GPU help? (Message 1388)
Posted 3 May 2014 by jasonp
Post:
NFS is a helluva drug...
7) Message boards : Questions/Problems/Bugs : Will using a GPU help? (Message 1386)
Posted 3 May 2014 by jasonp
Post:
SOE is a sieve in one dimension; GNFS requires a rectangular sieve (i.e. two-dimensional).

Honestly, I'm more interested in using GPUs for the postprocessing; this is a problem that using a botnet will not solve.
8) Message boards : Questions/Problems/Bugs : Will using a GPU help? (Message 1383)
Posted 3 May 2014 by jasonp
Post:
What other projects do is irrelevant. The client doesn't run on GPUs because nobody knows how to do that.

Take the Sieve of Eratosthenes. The inner loop of this algorithm is very similar to what a GNFS lattice sieve would have to do. An algorithm like this would have a hard time on a GPU because you are performing random updates to a huge array of bytes. GPUs have enormous memory bandwidth but this is a latency problem. Get SOE to run faster on a GPU than a CPU, say 10x faster, and I'll do the same with the client.
9) Message boards : Questions/Problems/Bugs : Will using a GPU help? (Message 1381)
Posted 2 May 2014 by jasonp
Post:
NFS@Home is entirely CPU based. Nobody knows how to move the computations that the client performs onto a GPU so that they run faster. This is a research problem, not a programming or money problem.
10) Message boards : Questions/Problems/Bugs : Prime Factor (Message 1218)
Posted 14 Dec 2013 by jasonp
Post:
NFS@Home pretty much only accepts numbers that have some sort of mathematical interest. I don't speak for Greg, but it's unlikely you'll convince anyone to break an RSA key for you.





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