distributed.net

distributed.net

URL	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 or GPU 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 and OGR-26 projects,^[3] which searched for 25- and 26-mark optimal Golomb rulers. The RC5-72 project is currently expected to exhaust the keyspace in just over 200 years, although the project will end whenever the required key is found. 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.

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 coordinated by Jeffrey A. Lawson, Adam L. Beberg, and David C. McNett along with several others who would serve on the board and operate infrastructure. By late March 1997 new proxies were released to resume RC5-56 and work began on enhanced clients. 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]

Portions of the source code for the client are publicly available, although users are not permitted to distribute modified versions themselves.^[12]

Development of GPU-enabled clients

• NVIDIA

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 300 million keys/second has been reported.^[13] 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 500%.^[14] At present, the CUDA clients are still under development, and have only obtained release candidate status.

• ATI

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. In the fall of 2009, ATI released the Evergreen GPU family, providing distributed.net with its most powerful processing engine ever. Some of the products in this series provide key rates in excess of 1.8 billion keys/second.^[15]

Timeline of distributed.net projects

Timeline of projects hosted by distributed.net, as of February 2011[update]

Current

• RSA Lab's 72-bit RC5 Encryption Challenge — In progress, 1.979% complete as of Nov 11, 2011^[16] (although RSA Labs has discontinued sponsorship)
• Optimal Golomb Rulers (OGR-27) — In progress, ~44.8% complete as of Nov 11, 2011^[17]

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)^[18]
• 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).^[19]
• 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^[20] (after 1552 days)
• Optimal Golomb Rulers (OGR-25) — Completed 25 October 2008^[21] (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

1. ^ "RC5-72 project page". distributed.net. http://www.distributed.net/rc5/. 
2. ^ "OGR-27 project stats". distributed.net. http://stats.distributed.net/projects.php?project_id=27. 
3. ^ "OGR project page". distributed.net. http://www.distributed.net/ogr/. 
4. ^ "RSA Laboratories Secret-Key Challenge". rsa.com. http://www.rsa.com/rsalabs/node.asp?id=2100. 
5. ^ "RC5-72 Continuation Announcement". distributed.net. http://n0cgi.distributed.net/cgi/planarc.cgi?user=bovine&plan=2008-09-08.02:09. 
6. ^ "distributed.net mailing list archive". http://lists.distributed.net/pipermail/rc5/2001-June/037127.html. 
7. ^ Glave, James (1997-03-03). "Macho Computing at Root of RSA Contest Flap". Wired. http://www.wired.com/news/technology/0,1282,2350,00.html. 
8. ^ "What's with all the cows?". distributed.net. http://faq.distributed.net/?file=80. 
9. ^ ^{a b} distributed.net "History & Timeline". distributed.net. http://www.distributed.net/history.php distributed.net. 
10. ^ "distributed.net completes rc5-64 project list announcement" (txt). distributed.net. 2002-09-26. http://www1.distributed.net/pressroom/news-20020926.txt. 
11. ^ "CPU Participation". distributed.net. http://stats.distributed.net/misc/platformlist.php?project_id=8&view=tco. 
12. ^ http://distributed.net/source/
13. ^ http://bugs.distributed.net/show_bug.cgi?id=4201
14. ^ http://en.wikipedia.org/wiki/Percentage_change
15. ^ "Benchmark results for Radeon HD 5870". MrJackson2000. April 1, 2010. http://arstechnica.com/civis/viewtopic.php?p=19780660&sid=19c2e0958c0248dfd2cae221f5e737c1#p19780660. 
16. ^ http://stats.distributed.net/projects.php?project_id=8
17. ^ http://stats.distributed.net/projects.php?project_id=27
18. ^ http://lists.distributed.net/hypermail/announce/0039.html
19. ^ http://distributed.net/csc
20. ^ "Plan entry by Greg Hewgill". 2004-11-01. http://n0cgi.distributed.net/cgi/planarc.cgi?user=gregh&plan=2004-11-01.23:48. 
21. ^ "distributed.net is proud to announce the completion of OGR-25!". 2008-10-26. http://www1.distributed.net/~bovine/plan/2008-10-25.23:14?user=bovine. 

External links

• Official website
• The RSA Laboratories Secret-Key Challenge (no longer active)