Which Key ID for Business Card?

[David Shaw]

On Jan 3, 2009, at 6:23 AM, Rippit the Ogg Frog wrote:

> Greetings, I just subscribed.
>
> I'm getting ready to have business cards printed, and want to  
> include my Key ID on them so that recipients can look up my key from  
> the keyservers.
>
> My old business card had the Key ID F7605786, UID crawford at goingware.com 
>   This is a 1024-bit key that I generated with the old Open Source  
> PGP way back when.
>
> But I have some hazy memory of generating a 2048-bit DSA key at some  
> point, which I think is the key one should use when sending me mail  
> these days.
>
> Given the following:
>
> $ gpg --fingerprint rippit at oggfrog.com
>
>
> pub   1024D/F7605786 1999-01-11
>  Key fingerprint = 9B9F 2D03 9996 AF83 9A4F  CB26 20E8 0D0B F760 5786
> uid                  Michael David Crawford (aka Rippit the Ogg Frog)
>                        <rippit at oggfrog.com>
> uid                  Michael David Crawford
>                        <michael at geometricvisions.com>
> uid                  Michael D. Crawford <crawford at goingware.com>
> sub   2048g/1EA551E9 1999-01-11
>
>
> Which is the Key ID to print on my business card? F7605786 or  
> 1EA551E9?

Neither.  You want the full fingerprint (9B9F 2D03 9996 AF83 9A4F CB26  
20E8 0D0B F760 5786).  Some people, myself included, include both the  
key ID (F7605786) as well as the full fingerprint.  Some people simply  
boldface the last 8 digits of the fingerprint, as the key ID is the  
same as the last 8 digits of the fingerprint.  However you choose to  
do it graphically, the point is that you want the large fingerprint as  
that is what (mostly) uniquely identifies your key.  The 8 digit key  
ID is just a cut-down version of that which is easier to type in.

> Or should I generate a new key entirely?

Your call on this one.  If your old key isn't widely signed by other  
people, you have nothing to lose in revoking it and making a new one.

David