Kenneth Lumia wrote:
>>> *'Defective' could mean a lot of things, certainly some type of EM zap 
>>> could kill them, but so could dropping it on the floor and stepping on it 
>>> with a hard shoe.
>>>
>>>
>>>       
>> simply bending the sticker based security tags stops them working pretty
>> often. My better half found this out when she was a "till jockey" and
>> the people tagging the items were breaking them
>> -- 
>>     
>
> Oh, come on now.  How unimaginative :)
>
> Zapping and crushing are so inelegant. This is the PIC list after all.
> These RFID devices will need a writable location to indicate they are
> "purchased/paid for".  Not that I'm suggesting that anyone do anything
> illegal or unethical, but it would be trivial to build a small RFID
> reader/writer that could fit into your pocket. Simply hold the item in front
> of you to deactivate it - no smashing or zapping required.
>
> >From what I've heard, the encryption on RFID is rather weak and not
> too difficult to figure out.  I saw a demo last week on TV.  The 
> demonstrator
> had a laptop with a small RFID reader (no writer) in a shoulder bag.
> He casually walked behind  the host and stood about 12 inches from
> the hosts back pocket.  The hosts wallet had a credit card with an RFID
> chip in it.  The demonstrator then pulled out the laptop and showed that
> the hosts name and credit card number were decoded (blurred out of course).
>
> Not good.  Not good at all!!!
>
> I don't know the RFID folks are going to make it secure and I'm really
> unhappy that I could become a walking collection of marketing and sales
> information.  As far as I know there are no laws against people "scanning"
> you to collect information :(
>
> Ken
> ____________________________
> ".... Do vector calculus just for fun"
> klumia@adelphia.net 
>
>
>   
I believe the general method of "deactivating" rfid stuff is to blow it
up, electrically speaking.
that or just mark those unique ID's as sold in the database.
the tags going into shops wont contain vast quantities of data, probably
just 256 bits worth of data
ie an ID

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