Source : Free On-Line Dictionary of Computing

brute force attack
     
         A method of breaking a cipher (that is, to
        decrypt a specific encrypted text) by trying every possible
        {key}.  The quicker the brute force attack, the weaker the
        cipher.  Feasibility of brute force attack depends on the key
        length of the cipher, and on the amount of computational power
        available to the attacker.  Brute force attack is impossible
        against the ciphers with variable-size key, such as a
        {one-time pad} cipher.
     
        {Breaking ciphers with many workstations
        (http://www.distributed.net/projects.html.en)}.
     
        (2000-01-16)