Longer passwords take longer to crack and offer better protection, say the researchers.
"Right now we can confidently say that a seven-character password is hopelessly inadequate," said Mr Boyd, "and as GPU power continues to go up every year, the threat will increase."
A better alternative, he suggested, would be a 12-character combination of upper and lower case letters, symbols and digits.
Ultimately, suggest the researchers, users may be forced to rely on whole sentences that are a mix of different sorts of characters to ensure no-one else can guess their password and get at online services.
GPGPU cracking increases need for stronger passwords
Posted on Thursday, Aug 19 2010 @ 12:17 CEST by Thomas De Maesschalck
BBC News reports short passwords are becoming increasingly insecure due to advances in GPGPU password cracking tools. A research team at Georgia Tech Research Institute says seven-character passwords are now hopelessly inadequate, and recommend people to use a 12-character (or longer) combination of upper and lower case letters, symbols and digits.