>>>>> "Ivan" == Ivan Popov <pin_at_medic.chalmers.se> writes:

    Ivan> In that sense all national passports are "global
    Ivan> identities".  We lack such ones in the computer world.

Do you think it was an accident that Microsoft called its attempt to
monopolize authentication services "Passport"?

But think about it.  A Coda token _is_ already a global identity in
the geographical sense.  It allows you to enter and travel within a
Coda realm according to your identity.

Also note that national passports are _not_ identities in the sense
that a computer login is an identity.  If you fake my passport, you
can travel from one country to another as me, but you will have a hard
time accessing my bank accounts or giving grades to my students.  By
contrast, in most cases once you are authenticated on a system, you
get "all the honors and privileges appertaining to the degree" as my
high school diploma says.

I guess my meaning is that this is a hard problem, and we should be
very careful about analogies to "real world" contructs like passports
when talking about authentication on computer systems.

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