One Time Identification, a request for comments/testing. g.w at
Fri Feb 2 14:10:07 EST 2007

On Feb 1,  5:15pm, Jeffrey Hutzelman wrote:
} Subject: Re: One Time Identification, a request for comments/testing.

Good day to everyone.

> On Thursday, February 01, 2007 03:06:21 PM -0600 g.w at wrote:
> >> What keeps a user from copying the identity token from the USB
> >> device to a local or shared file system to avoid having to insert
> >> the USB device all the time?
> >
> > We were considering public flogging but were unsure if we could get it
> > into an IETF draft.

> <wg chair hat on>
> Anyone can submit an internet-draft; just write up your proposal
> according to <> and send
> it off to internet-drafts at
> You should then bring up your proposal on the Kerberos Working Group
> mailing list, ietf-krb-wg at  We're beginning to move into the
> area of preauthentication and improving the initial authentication
> exchange, and while I can't guarantee that your proposal will be
> well-received, it will certainly receive the same consideration as a
> number of others that have recently been raised.

I do appreciate the offer and will review the proposal guidelines.

That being said I'm certainly no IETF politician.  I also don't have
any agenda, corporate or otherwise with any of this.  I believe there
needs to be people doing interesting stuff in this field and I enjoy
the challenge of innovation.  Its not sexy, nor fun, like building a
new desktop environment so there is a paucity of Open-Source interest
in the arena.

OTI ultimately comes from our work and interest in how to define
identity.  As such its a paradigm shift which is always a difficult

But we would certainly entertain a discussion if anyone was interested
in any type of collaboration on this.

> > Security starts with user training and making it unnecessary for them
> > to want to do things like that.
> In this case, I think that is unrealistic.  The thing users want to
> avoid is "Oh, damn, I have to dig out this stupid USB thing and plug
> it in before I can use my computer, what a pain."  They'll do that
> by copying the file off, especially after the first few instances of
> "Oh, damn, I have to dig out this stupid USB thing and plug it in to
> use my laptop, and I can't because I'm in Europe and the USB thingy
> is in Pittsburgh".

Luckily there is a sure and certain solution to the problem.  Spend
money implementing CryptoCard or any one of a number of other
solutions which people will gladly sell you.

The only organizational challenge is dealing with the user who forgot
their CryptoCard the last time they flew to Europe and now have it
securely duct taped to the back of their laptop, with the pin number
written in magic marker on the duct tape so they don't forget it.

Jeff, you and I have been doing this stuff for a long time.  I think
we both agree its not possible to technically erradicate stupidity.

There is an understandable fixation about copying off the identity
token.  I think the reason for it is the issue of paradigm shift which
I discussed above.  Physical protection of a two factor token arises
from a paradigm where the token is capable of independently
implementing the user's identity.

Thats why RSA private keys get stuffed inside a self-destructing card
or device, to force direct physical possession of the identity
implementation.  There is still a secret which ties implementation of
the identity to a user, only we call it a PIN number rather than a

In OTI the paradigm shifts, the implementation of the identity
involves a direct interaction between the token and the user's secret
(key).  Obviously one prefers not to have tokens go wandering about,
that is a standard security predicate of attacker knowledge
deprivation.  But, and its an important but, the token is not
independently capable of implementing the user's identity.

So Jeff, your IDtoken is free to go to Europe inside your laptop.
Interestingly, it avoids a Denial of Service (DOS) attack from the
person whose draft you frowned on, who decided to punch 0-0-0-0 into
your CryptoCard four times to make your life miserable in Europe.

I'm assuming, of course, standard security policy which requires a
trip to the HelpDesk with a picture ID in the event of a need to
re-establish authentication for someone... :-)

> -- Jeffrey T. Hutzelman (N3NHS) <jhutz+ at>

--..., ...--

Best wishes for a pleasant weekend.

}-- End of excerpt from Jeffrey Hutzelman

As always,
Greg Wettstein

			 The Hurderos Project
         Open Identity, Service and Authorization Management

"Everything should be made as simple as possible, but not simpler."
                                -- Albert Einstein

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