Team Cracks RSA Encryption Challenge
Source: E-Week
A worldwide team of volunteers, using spare computing power, found the secret key for a message encrypted with the RC5-64 cipher, winning a $10,000 prize and, they say, casting some doubt on the security of messages protected by the cipher.
Distributed.net, a collection of more than 331,000 volunteers who lent their machines' idle processing power to the effort, solved the challenge posed in 1997 by RSA Laboratories, the research arm of RSA Security Inc. It took nearly four years, a search through 15,769,938,165,961,326,592 keys and processing power roughly equivalent to nearly 46,000 2GHz AMD Athlon machines for the team to find the correct key.
The plaintext message that the key unlocked was: "Some things are better left unread."
A 450MHz Pentium III machine in Japan found the key on July 14, but a technical glitch prevented the Distributed.net team from realizing they had the correct key until Aug. 12.
The team's organizers said their effort should not only prove the effectiveness of distributed computing efforts in solving large problems but also cause people to think twice before using the 64-bit RC5 cipher to encrypt some data.
"While it's debatable that the duration of this project does much to devalue the security of a 64-bit RC5 key…we can say with confidence that RC5 is not an appropriate algorithm to use for data that will still be sensitive in more than several years' time," the team said in a statement.
