Info needed on observers

[lvhove&vnet3.vub.ac.be@vnet3.vub.ac.be (Leo Van Hove)]

                               ////
                              (. .)
___________________________o00-(_)-00o___________________________________

Hi,

I am currently preparing a paper on payment systems for the Internet
and related issues.  I recently found out that so-called observers could
be placed on smart cards (in order to prevent double spending, or even to
prevent people from cheating on taxes...).

To be honest that's about all I know about observers and I am very eager
to find out more.  I am, however, having a hard time finding interesting
references on this subject.

Hence, all suggestions to get me started would be extremely welcome.
Questions of particular interest are: possible functions (and limits),
how 'real' are they already?, what about privacy?, ...

Many thanks in advance.

leo

_________________________________________________________________________
Leo Van Hove

Centre for Financial Economics
Vrije Universiteit Brussel (Free University of Brussels)
Pleinlaan 2
B-1050 Brussels
Vox: +32 629.21.25
Fax: +32 2 629.22.82
e-mail: lvhove@vnet3.vub.ac.be
_________________________________________________________________________