From: "Michael Scott" Newsgroups: sci.crypt,sci.math Subject: Factoring Date: Fri, 8 Jan 1999 19:37:43 -0000 15 years ago the biggest "difficult" number to be factored (that is the product of two large primes) was (10^71-1)/9. This record factorisation was acheived by Davis & Holdridge at Sandia National Laboratories, requiring 9.5 hours on a Cray XMP. Things have of course moved on since, but the standard Home Computer has finally caught up, and this number can now be factored in about 5 hours or less on the basic 266MHz, 32Mb Pentium box. So, announcing an updated version of my free Windows NT/'95 Command Prompt factoring program ftp://ftp.compapp.dcu.ie/pub/crypto/factor.exe This 32-bit program uses 6 different factoring algorithms, culminating in the multiple polynomial quadratic sieve. This latter uses a lot of memory for bigger numbers. However don't expect to set records - modern factoring algorithms parallelise almost perfectly, so records are set on networks of computers working together, not on solo workstations. -- Mike Scott ----------------------------------------- Fastest is best. MIRACL multiprecision C/C++ library for big number cryptography http://indigo.ie/~mscott ============================================================================== From: "Michael Scott" Subject: Re: Factoring Date: Sat, 9 Jan 1999 12:53:12 -0000 Newsgroups: sci.crypt,sci.math So download the source from ftp://ftp.compapp.dcu.ie/pub/crypto/miracl.zip and compile it yourself! I recommend Borland C V4.5. Find the file factor.c and the library bc32.lib, copy the header files miracl.h and mirdef.h32 (renamed to mirdef.h) to ....\bc45\include\, and compile as:- bcc32 factor.c bc32.lib Mike Scott Hub-R-ISS-1 wrote in message <36972e77.0@bn.ar.com.au>... >I'd just like to repeat the warning against downloading .exe files from even >slightly suspect sites. > >