as of 8 Nov 2022 (although RSA Labs has discontinued sponsorship) 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 23 February 1998 (after 39 days) RSA Lab's 56-bit DES-II-2 Encryption Challenge — Ended 15 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). RSA Lab's 64-bit RC5 Encryption Challenge — Completed 14 July 2002 (after days and 83% of the key space tested). Golomb rulers Optimal Golomb Rulers (OGR-24) — Completed 13 October 2004 (after days, confirmed predicted best ruler) Optimal Golomb Rulers (OGR-25) — Completed 24 October 2008 (after days, confirmed predicted best ruler) Optimal Golomb Rulers (OGR-26) — Completed 24 February 2009 (after days, confirmed predicted best ruler) Optimal Golomb Rulers (OGR-27) — Completed 19 February 2014 (after days, confirmed predicted best ruler) Optimal Golomb Rulers (OGR-28) — Completed 23 November 2022 (after days, confirmed predicted best ruler) See also RSA Secret-Key Challenge Golomb Ruler DES Challenges Brute force attack Cryptanalysis Key size List of volunteer computing projects Berkeley Open Infrastructure for Network Computing References External links Official website Cryptographic attacks Volunteer computing projects Charities based in the United States Organizations established in 1997 Articles which contain graphical timelines