Breaking 768-bit SNFS

Lattice Siever for (2^773)+1

Dear Lattice Siever,

Please try the code/binaries below. If we've discussed switching to the most recent version of the code, it's available here. (The main new feature changes the way max_reports is handled, keeping it set at 41; and the WIN_32 version has a more agressive nicing setting to keep the program out of your way during the day. Again, if you're using 64Mb (or 42Mb) and haven't gotten any error messages X*.NFO, please see below instead.)

Dear ECC2K-108 participant,

Try the instructions below to see whether you can get a running copy of the siever. The program wants 64Mb of RAM for itself. If you have under 128Mb of RAM, but are willing to run at half speed, you may be able to get the program to run reasonably well (enough for evenings and weekends) using 42 Mb. For W95/W98/NT users, Arjen's binary is available here, and you'll also need to build the factor bases (as described below) using the binaries ratbase and algbase. For pc/LINUX users with pentium or above, Jeff Gilchrist has prepared the zip file here, which has all three binaries, as well as shell scripts for running the program.

The code compiles on all Alpha OS's that we've tried so far (please let us know if it doesn't on yours!). We expect the code to run on most SUNs.

Once you have a running binary, email me at telling me how many cpus you expect to run, and I'll send you back a range for sieving. (This is a temporary measure, until we're better setup for automatic running.)

Dear cabalist,

If you expect to need (new) copies of all of the files, you may ignore the step-by-step instructions below and click here. There are 12 program files and a single unified instruction file.

NOTE: All programs and initialization files are copyright Arjen K. Lenstra, as indicated.

Long Integer Package:

If you don't already have a copy of lip.o, click here. There are 3 program files and a compile instruction. This output file is needed for all of the following, so if you're having trouble at this step you should consider picking up a compiled binary of bbbg0, above, or consulting a cabalist with experience using your compiler.

Factor Base Programs:

If you don't already have a copy of ratbase and algbase, click here. There are 3 new program files and two compile instructions. (If your copy of lip.o is OK, this step should be easy.)

Siever and Factor Bases:

Now that you have lip.o, ratbase and algbase, click here. There's a new program file (the siever!) and three instructions. (The crucial step ...)

Test File(s):

To pickup an initial test file, and see what the output is supposed to look like, click here. There's also a program to check your timings.

Check out a sieving range (and decide how you'll send in your data):

TBA ...

B. Dodson, Revised March 6, 2000.