Difference between TCPA-Hardware and a smart card (was: example:secure computing kernel needed)

[Ian Grigg]

Bill Stewart wrote:
> 
> >At 09:38 AM 12/16/2003 -0500, Ian Grigg wrote:
> >
> >>In the late nineties, the smart card world
> >>worked out that each smart card was so expensive,
> >>it would only work if the issuer could do multiple
> >>apps on each card.  That is, if they could share
> >>the cost with different uses (or users).
> 
> Of course, at this point the assertion that a smart card
> (that doesn't also have independent user I/O)
> costs enough to care about is pretty bogus.
> Dumb smartcards are cost-effective enough to use them
> to carry $5 in telephone minutes.


Sorry, yes, each actual smart card is, at
the margin, cheap.  But, as a project, the
smart card is expensive.  There's a big
difference between project costs and the
marginal cost, and that generally makes
*the* difference.

I suppose the confusion is endemic;  as
everyone thinks about the project costs in
terms of "per person" and this is considered
by assumption to be one smart card per person,
but the cost per person is not the single 50c
per actual smart card.

Smart cards are a lot like Christmas, it's
not the gift, but the act of giving that
makes it special.

> The real constraint is that you're unlikely to have
> more than one card reader in a machine,
> so multifunction cards provide the opportunity to
> run multiple applications without switching cards in and out,
> but that only works if the application vendors cooperate.
> 
> For instance, you may have some encrypted session application
> that needs to have your card stay in the machine during the session
> (e.g. VOIP, or secure login, SSH-like things, remote file system access),
> and you may want to pay for something using your bank smartcard
> during the session.  That's not likely to work out,
> because the secure session software vendors are
> unlikely to have a relationship with your bank that lets
> both of them trust each other with their information,
> compared to the simpliciy of having multiple cards.


For example, yes.  So it all comes down to
whether you can afford to role out the hardware
to all the vendors, and all the associated
nodes.  At this point, the penny drops, and
smart cards start looking very expensive.

Hence, to date, only single-purpose projects
have succeeded - ones where the economics
where clearly based on narrowly focused,
single activities:  phones, transit systems,
etc, and they justified themselves on those
activities, alone, without relying on the
economics of unmeasurable and unmeetable
hyperbole.

iang

PS: all those Europeans with all those
smart cards in their pockets - ask them
how many times they use the smart card
features!

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