January 7, 2010 5:20 PM<\/abbr><\/em><\/div>\nWith the increasing computing power available to even casual users, the security-conscious have had to move on to increasingly robust encryption, lest they find their information vulnerable to brute-force attacks. The latest milestone to fall is 768-bit RSA; in a paper posted on a cryptography preprint server, academic researchers have now announced that they factored one of these keys in early December.<\/p>\n
Most modern cryptography relies on single large numbers that are the product of two primes. If you know the numbers, it’s relatively easy to encrypt and decrypt data; if you don’t, finding the numbers by brute force is a big computational challenge. But this challenge gets easier every year as processor speed and efficiency increase, making “secure” a bit of a moving target. The paper describes how the process was done with commodity hardware, albeit lots of it.<\/p>\n
Their first step involved sieving, or identifying appropriate integers; that took the equivalent of 1,500 years on one core of a 2.2GHz Opteron; the results occupied about 5TB. Those were then uniqued and processed into a matrix; because of all the previous work, actually using the matrix to factor the RSA value only took a cluster less than half a day. Although most people aren’t going to have access to these sorts of clusters, they represent a trivial amount of computing power for many organizations. As a result, the authors conclude, “The overall effort is sufficiently low that even for short-term protection of data of little value, 768-bit RSA moduli can no longer be recommended.” 1024-bit values should be good for a few years still.<\/p>\n
Given that these developments are somewhat inevitable, even the authors sound a bit bored by their report. “There is nothing new to be reported for the square root step, except for the resulting factorization of RSA-768” they write. “Nevertheless, and for the record, we present some of the details.” Still, they manage to have a little fun, in one place referencing a YouTube clip of a Tarantino film following their use of the term “bingo.”<\/p>\n","protected":false},"excerpt":{"rendered":"
Researchers have posted a preprint that describes their method for factoring a number used for RSA 768-bit encryption. SOURCE: By John Timmer | Last updated January 7, 2010 5:20 PM With the increasing computing power available to even casual users, the security-conscious have had to move on to increasingly robust encryption, lest they find their…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[13],"class_list":["post-67","post","type-post","status-publish","format-standard","hentry","category-general","tag-encryption","content","has-not-featured-image"],"yoast_head":"\n
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