As computing power has increased, the available horsepower to brute force crack RSA algorithms has grown as well. The most recent announcement, in December 2009, was that a group of mathematicians, computer scientists and cryptographers had managed to factorise a 768-bit RSA key using a technique called the number field sieve or NFS. That puts the next milestone, the 1024-bit RSA key, in reach in the next decade or so.

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