"Matthew" wrote in message
om...
I am interested in the mechanics of these cards, which are smart cards
for use on London's transport system. One would hope given the
reported £1billion+ that they are secure.

This is funny: "Because the Oyster card is contactless, customers only need
to touch the cardreaders with their Oyster cards as they pass through ticket
gates at London Underground or National Rail stations or board a bus. "

If they are contactless, then whey do the customers need touch the
cardreaders?

Here's a bit of info on the cards themselves:
http://rapidttp.com/transponder/presre13.html

I have one similar (dumb card) produced by honeywell for my work badge. It
simply contains an eprom with an embedded code, which is activiated when
swiped near a transponder containing an EM field. The transponder reads the
code, sends the information to a computer which then decided whether or not
to unlock the door. (Oddly enough I have no physical access to the
mainframe. Probably a good idea.)

I read recently that Phillips - who makes the Oyster card - is going to roll
these out in a massive scale in China for transportation purposes.

K (Smile, you're happy now.)