Generating a new key

[David Shaw]

On Mar 21, 2010, at 12:29 AM, Doug Barton wrote:

> On 03/20/10 20:28, David Shaw wrote:
>> On Mar 20, 2010, at 9:09 PM, Doug Barton wrote:
>> 
>>> Capabilities: SCA I don't have a particular need for an
>>> authentication key atm, but I might someday, and I'd really rather
>>> avoid a proliferation of new keys, subkeys, etc. I'm aiming to make
>>> this my one key for another good long while. If I get 7 years out
>>> of this one (like I did my DSA key) that'll be a good achievement I
>>> think.
>> 
>> I wouldn't do this.  The default is SC (sign+certify).  If you want
>> an authentication key at some point in the future, I recommend a
>> subkey.  If you make your primary key the authentication key, you
>> need to have that key online, and lose the ability to store it
>> offline someday.
> 
> I thought about that actually, and was unclear about two things. It
> doesn't seem to me that an authentication key would need signatures, is
> that correct? The other is in reference to what you said above. If I add
> an authentication subkey is it possible to store just the subkey
> separate from the "main" SC key? I'm familiar with the concept of
> on-line vs. off-line keys and fairly familiar with the security
> implications relative to my work with DNSSEC, just not sure how they
> relate here.

GnuPG supports an offline key setup where the primary key is kept offline and the subkeys are kept online (and yes, you can store an authentication subkey separate from the main key).  This works very well for the common OpenPGP case where the primary key is the most important one (as it is used to certify new subkeys, among other things).  If you lose/compromise/etc your online subkeys, just use the offline primary to revoke them and make new subkeys.  The primary isn't kept with the subkeys, so it is much less likely to be lost/compromised along with them.

David