Contactless bank cards

Peter Tomlinson pwt at
Thu Nov 18 07:05:03 GMT 2010

Roland Perry wrote:
>> The technology is dozens of order of magnitude away from
>> scanning the bus pass in the passenger's pocket as he gets on board.
There IS a longer distance scanning technology, but it depends on 
changing to a self-powered token instead of an unpowered smart device 
that needs the associated terminal to provide the smart device's power 
[1]. There is also a risk that mobile phone based methods using NFC 
technology will wake up the tokens when the field strength from the 
terminal is lower than needed to wake up an ordinary smart card - but 
with NFC you should be getting a message on the phone's screen (and 
maybe a squeal as well) to show that a value transaction has taken place.


[1] Be-In Be-Out (BiBo) and Check-In Be-Out (Cibo). See DfT research report:

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