RSA key size restriction?

[Malte Gell]

Am Dienstag, 9. Dezember 2003 09:18 schrieb Ludwig Hügelschäfer:
> Hello,
>
>  > Why is the RSA support in GnuPG limited keysizes <= 4096 bits?
>
> I think, one should limit the size to reasonable sizes.

What is a reasonable size? I think a 4096 bit RSA key provides security 
that may be far beyond what most people need. But think of a 30 year 
old human rights activist in a dictatorship, "they" may use force to 
get the information they want, but it may be possible they just collect 
every encrypted communication and wait until it's feasible to reveal 
the information and so the life of this person can be endangered 20, 30 
years later. Can you guarantee that a 4096 bit key will still be safe 
in 3,4 decades from now? With a 8k or even 16k key the probability 
would certainly be much higher.
Though, only very few people may need such security for them it'd be 
nice to be sure that their information are kept secret as long as they 
live and beyond... Maybe, such key sizes would be a nice extension for 
the --expert option :-)