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Submission + - 512-bit RSA factoring in your spare time (

An anonymous reader writes: The 512-bit RSA signing keys for several Texas Instruments (TI) calculators have been factored, allowing the installation of custom software, including operating systems. A forum member at reportedly used sophisticated factoring software developed by the open source GGNFS and Msieve projects. After the original poster cracked the key for the TI-83, the community mounted a distributed computational effort, quickly obtaining several more keys. Also mentioned were some interesting statistics:

-The factorization took, in total, about 1745 hours, or a bit less than 73 days, of computation. (I've actually been working on this since early March; I had a couple of false starts and haven't been able to run the software continously.)
-My CPU, for reference, is a dual-core Athlon64 at 1900 MHz.
-The sieving database was 4.9 gigabytes and contained just over 51 million relations.
-During the "filtering" phase, Msieve was using about 2.5 gigabytes of RAM.
-The final processing involved finding the null space of a 5.4 million x 5.4 million matrix.

This case is particularly notable, as the goal was to compromise live keys. Furthermore, the goal was accomplished using modest resources within only a few weeks. Invoking the DMCA, TI immediately moved to suppress the propagation of the keys, resulting in an even wider distribution.

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512-bit RSA factoring in your spare time

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