How to make a security geek feel very old: #Factorisation, #DKIM and @DrZacharyHarris
“A 384-bit key I can factor on my laptop in 24 hours. The 512-bit keys I can factor in about 72 hours using Amazon Web Services for $75. And I did do a number of those. Then there are the 768-bit keys. Those are not factorable by a normal person like me with my resources alone. But the government of Iran probably could, or a large group with sufficient computing resources could pull it off.” Remember when we thought 512-bit keys would be enough? how time flies! Of course, John Aycock raised this problem back in 2007, although he assumed it’d take a 100,000-host botnet to crack them (in 153 minutes).
(tags: factorisation moores-law cpu speed dkim domain-keys 512-bit cracking security via:alec-muffet)