Secure Messaging in Ubuntu

[Tony Arnold]

Gene,

On 08/09/13 16:16, Gene Heskett wrote:

> 2048 bit, 256 8 bit chars, is today a small key however, so I would suggest 
> that a new key std be established, as much to accommodate the variety 
> without duplication, by squaring it to 65536, which would then be a 524,288 
> bit key.  That, FWIW, was assumed in the above total.

Such a large key would be made up of the product of two quite large
prime numbers? I don't know the details but I believe there is a largest
known prime number or at least few known very large prime numbers (and
they seem to get sparser the larger they are), in which case having an
extremely large key may reduce the choice of keys and thus make it
almost trivial to crack? Or am I missing something?

Regards,
Tony.
-- 
Tony Arnold,                        Tel: +44 (0) 161 275 6093
Head of IT Security,                Fax: +44 (0) 705 344 3082
University of Manchester,           Mob: +44 (0) 773 330 0039
Manchester M13 9PL.                 Email: tony.arnold at manchester.ac.uk