[extropy-chat] RFID smartcard passports and driver's licences

Dan Clemmensen dgc at cox.net
Thu Apr 7 01:03:11 UTC 2005

Mike Lorry wrote:

>>RFID chips are unpowered until brought into the vicinity of the
>>So they can't do too much monitoring of routine activities.  The main
>>thing they could store is a record of when and how they had been
>>activated in the past.
>Not even that. They are rather stupid in that way, and are
>intentionally designed to be stupid so that the posessor can never
>figure out even with technical assistance how frequently they are being
I assume this is true. It is certainly technically feasible. However, I 
thought the reason RFID tags are "dumb" is that the target price per tag 
is below five cents, and not for any nefarious reason.

If any real percentage of the consuming public is bothered by this then 
the scheme will be defeated, because someone will market a cheap 
portable scan logger. Anyone who is interested in when they are scanned 
will not rely on the the dumb RFIDs in the wallet, but
will instead carry the smart scan logger. If it becomes public knowledge 
that a certain profile makes you a "preferred customer" in a store, then 
that profile will very rapidly become widely deseminated, and consumers 
will program the profile into their smart loggers so that the logger 
will respond to a scan with the appropriate set of RFID info.

This scheme will work because the transaction initiator ( the store's 
scanner in this case) must make itself known first: this in inherent in 
the RFID concept. No information flows until the scanner announces its 

This is the reason that Radar and active Sonar are rarely used in modern 
war games. Your Radar and active sonar tell you a great deal about the 
enemy, but they tell the enemy a great deal more about you.

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