BBC Moneybox - contactless hiccups

Chris Edwards chris-ukcrypto at
Mon May 20 10:49:44 BST 2013

On Mon, 20 May 2013, Roland Perry wrote:

> What if the contactless credit card is adjacent to an Oyster or ITSO card in
> your wallet?

$workplace uses a mifare card based entry system (wave your wallet 
containing card at door reader).  Last year, I started frequently having 
problems opening doors.  Then I realised this was due to my bank having 
issued a new visa card, which has the "pay-by-wave" logo (looks a bit like 
a WiFi symbol).  Removing this visa card from my wallet reinstated by 
ability to open doors.

I had some idea the protocols specifically catered for multiple cards, and 
that the door card reader would be able to "select" the card it wants to 
talk to.  But if so, this doesn't seem to work very well (for me).

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