[Discuss] KeePassX

[kentborg at borg.org (Kent Borg)]

On 08/13/2013 10:43 AM, Jack Coats wrote:
> Guess that is why I like the idea of 4096 bit keys.

At 4096 I think you are talking about RSA or similar asymmetrical keys.  
Symmetrical keys are far smaller for similar strength.  The strength of 
symmetrical keys are also far easier to estimate, and less susceptible 
to breakthroughs in quantum computing or other likely magic.

In practice a 4096-bit key is only used to send a far smaller 
symmetrical key, and that key is only used for that one session, but all 
the real data is encrypted using that key, using something like AES.

Passphrases that humans might be expected to accurately type are 
analogous to symmetrical keys.  Accurately typing anything that is 
equivalent to just 128-bits is hard, at least if you are typing it 
blindly (with nothing but bullet characters typed back at you) and can't 
see and correct your mistakes.

-kb