Distributed.net

distributed.net

URL	http://www.distributed.net/
Type of site	volunteer computing
Owner	Distributed Computing Technologies, Inc.
Launched	1997

distributed.net (or Distributed Computing Technologies, Inc. or DCTI) is a worldwide distributed computing effort that is attempting to solve large scale problems using otherwise idle CPU time. It is officially recognized as a non-profit organization under U.S. tax code 501(c)(3).

Currently, distributed.net is working on RC5-72 (breaking RC5 with a 72-bit key)^[1], OGR-27^[2] and also has recently completed the OGR-25 & 26 projects^[3], which searched for 25 and 26 point optimal Golomb rulers. RC5-72 has an expected completion date of over one thousand years. Both problems are part of a series— OGR is part of an infinite series; RC5 currently has eight unsolved challenges from RSA Security, although in May 2007, RSA Security announced^[4] that they would no longer be providing prize money for a correct key to any of their secret key challenges. distributed.net has decided to sponsor the original prize offer for finding the key as a result.^[5]

In 2001, distributed.net was estimated to have a throughput of over 30 TFLOPS.^[6] Current throughput is likely to be much higher.^{[citation needed]}

History

A coordinated effort was started in February 1997 by Earle Ady and Christopher G. Stach II of Hotjobs.com and New Media Labs fame, as an effort to break the RC5-56 portion of the RSA Secret-Key Challenge, a 56-bit encryption algorithm that had a $10,000 USD prize available to anyone who could find the key. Unfortunately, this initial effort had to be suspended as the result of SYN flood attacks by participants upon the server.^[7]

A new independent effort, named distributed.net, was later coordinated by Jeff Lawson in March 1997 to resume the effort. A cow head was selected as the icon of the application and the project's mascot.^[8] The RC5-56 challenge was solved on October 19, 1997 after 250 days.^[9]

The next project was the RC5-64 challenge which took nearly five years to complete before the correct key (0x63DE7DC154F4D039) was found on July 14, 2002 decrypting the message to the plaintext "some things are better left unread".^[10]

The distributed.net client

"dnetc" is the file name of the software application which users run to participate in any active distributed.net project. It is a command line program with an interface to configure it, available for a wide variety of platforms. distributed.net refers to the software application simply as the "client". As of May 2009^[update], 32-bit Windows on Intel x86 is the most used configuration, with Linux on Intel x86 in second place, and Mac OS X on PowerPC in third place.^[11]

Development of GPU-enabled clients

Beginning in late 2007, work began on the implementation of new RC5-72 cores designed to run on NVIDIA CUDA enabled hardware. The CUDA parallel computing architecture enables high-speed processing of RC5-72 work units. On high-end NVIDIA video cards, upwards of 500 million keys/second has been reported.^[12] Considering a very high end single CPU working on RC5-72 may achieve 50 million keys/second, the CUDA advancement represents a performance increase of roughly 900%.^[13] At present, the CUDA clients are still under development, and have only obtained pre-release status.

Similarly, near the end of 2008, work began on the implementation of new RC5-72 cores designed to run on ATI STREAM enabled hardware. STREAM allows for high-speed processing of RC5-72 work units in a manner comparable to CUDA. STREAM clients are still in their infancy, and have only obtained pre-release status.

Timeline of distributed.net projects

Timeline of projects hosted by distributed.net, as of May 2009[update]

Current

• RSA Lab's 72-bit RC5 Encryption Challenge — In progress (although RSA Labs has discontinued sponsorship)
• Optimal Golomb Rulers (OGR-27)

Cryptography

• RSA Lab's 56-bit RC5 Encryption Challenge — Completed 19 October 1997 (after 250 days and 47% of the key space tested).
• RSA Lab's 56-bit DES II-1 Encryption Challenge — Completed 24 February 1998 (after 39 days)^[14]
• RSA Lab's 56-bit DES II-2 Encryption Challenge — Ended 17 July 1998 (found independently by the EFF DES cracker after 2.5 days)
• RSA Lab's 56-bit DES-III Encryption Challenge — Completed 19 January 1999 (after 22.5 hours with the help of the EFF DES cracker)
• CS-Cipher Challenge — Completed 16 January 2000 (after 60 days and 98% of the key space tested).^[15]
• RSA Lab's 64-bit RC5 Encryption Challenge — Completed 14 July 2002 (after 1757 days and 83% of the key space tested).^[9]

Golomb Rulers

• Optimal Golomb Rulers (OGR-24) — Completed 13 October 2004^[16] (after 1552 days)
• Optimal Golomb Rulers (OGR-25) — Completed 25 October 2008^[17] (after 3006 days)
• Optimal Golomb Rulers (OGR-26) — Completed 24 February 2009 (after 122 days)

See also

• RSA Secret-Key Challenge
• Golomb Ruler
• DES Challenges
• Brute force attack
• Cryptanalysis
• Key size
• List of distributed computing projects

References

External links

• Official website
• The RSA Laboratories Secret-Key Challenge (now closed)