Re: Key Escrow Good, GAK Bad

["William H. Geiger III" <whgiii@amaranth.com>]

-----BEGIN PGP SIGNED MESSAGE-----


In <199701092357.PAA23840@slack.lne.com>, on 01/09/97 at 07:57 PM,
   Eric Murray <ericm@lne.com> said:


>Ken Kirksey writes:
>> 
>> >  To me, Key Recovery cryptography is like using a condom with a
>> >hole in it. No thanks.
>> 
>> I agree in principle, and I doubt I would ever use a key recovery system 
>> if I had a choice.  But, speaking as a network manager, I know that 
>> private key recovery (not GAK) can be an enhancement to security.  
>> 
>> I'll give an example.  About a year ago, my boss wanted to protect his 
>> file of annual financial projections for the company from prying eyes on 
>> our Macintosh network.  I installed CurveEncrypt on his machine, showed 
>> him how to use it, and gave him the standard lecture on choosing a good 
>> passphrase.  I stressed that he needed to chose a passphrase easy to 
>> remember, because if he forgot it, there was no way to get his file back.
>> 
>> Well, he forgot his passphrase.  He spent an hour trying every 
>> combination he could think of, interjecting a curse here and there for 
>> color.  He is now totally off using encryption to protect sensitive 
>> information.

>User education would be even easier than key escrow.  Your boss could
>have shared that passphrase with one or more other people, ideally the
>people who helped him make the report.  When you encrypt something
>that's vital to the company, you need to make sure that it can be
>gotten back.  In most companies, there's more than one person who
>is 'cleared' for even the more vital information.  The keys to
>those files should be shared amongst those people.

>Unfortunately, few encryption programs make this easy.  And even though
>you can do it in PGP by encrypting to multiple recipients, how many
>people think to do so?  I don't.  Most programs assume that there's one
>key that that's used to encrypt everything, hence one level of security-
>the highest.  But in a business situation you really need to be able to
>encrypt something with your key and your secretary's key, or the keys of
>all the board members, etc.

Would not this be the perfect senario for the implementation of Shamir's Secret Sharing?
Rather that having several people being able to access the data
independent of each other having a shared key where it requited say 3 out of
5 members to access the data?

That way a breach of security of one key does not result in a breach of security of all
data.

Are there any know implementations of this?

Thanks,



- --
- -----------------------------------------------------------
William H. Geiger III  http://www.amaranth.com/~whgiii
Geiger Consulting    WebExplorer & Java Enhanced!!!
Cooking With Warp 4.0

Author of E-Secure - PGP Front End for MR/2 Ice

Look for MR/2 Tips & Rexx Scripts
Get Work Place Shell for Windows!!
PGP & MR/2 the only way for secure e-mail.
                          
Finger whgiii@amaranth.com for PGP Key and other info
- -----------------------------------------------------------
 
Tag-O-Matic: Air conditioned environment - Do not open Windows.

-----BEGIN PGP SIGNATURE-----
Version: 2.6.2

iQCVAwUBMtXo/49Co1n+aLhhAQEZ3QP7BSwuDC7OyXpNPGg8HtROkHkMTpIP6oBf
S/NvqazKt8PFsnmpY0m2aCaZzHUOSD5d42tOVxZr8xJK7ylm/DIbwACgRtGDL6yT
61RUn4c8kXoS8bKOCRWyQvcyZJWSy4ddcnTlj/y7zbmmKOqvxdWWf333+NvWsbG1
xpcsm6n7sy4=
=v0Q6
-----END PGP SIGNATURE-----