On 17/09/2014 19:56, Roland Perry wrote:
In message , at
19:32:32 on Wed, 17 Sep 2014, Arthur Figgis
remarked:
If I can by a coffee at Starbucks by waving a CPC, and it ends up on my
bill at the end of the month, it does seem as if waving a CPC at a gate
ought to register my presence with enough information to bill me
overnight once I've also registered a touch-out. But clearly it's all a
lot more complicated than that, given the kerfuffle to get it all in
place.

Because Starbucks knows how much to charge you before you wave your
card, but TfL doesn't know whether you will make more journeys today.

You've missed the point. The TfL gates "know" to charge you £0, and send
that message along with your location back to HQ. At the end of the day
someone looks at all the £0 charges and works out where you've been and
what non-zero charge to apply to the cardholder.

Which is only possible because TfL et al sat down and devised a system
of charging people £0. Coffee shops don't tend to do that, they charge
per transaction. I rarely use Starbucks, but I'd be surprised if it
tells a database somewhere what drinks you have had each day and then
the database calculates the price at the end of the week.

(I also doubt "someone" looks at it!)


Readers in shops can occasionally ask you for a PIN, but ticket gates
can't do that. This means new rules were needed,

That's a completely different bit of governance work which the card
companies claim was done years ago (at least two years for acceptance on
buses, obviously).

Same project.

as well as new software.

Not really, the terminals just have to desist from asking for a PIN if
they don't have a keyboard. That was sorted for acceptance on buses in
2012.

The Oyster terminals have presumably never been told to ask for PINs,
but the contactless system apparently needed them.

TfL also controls all(?) the buses (and carries revenue risk?), while
DfT controls (most of) the trains and has to agree to the contracts.
--
Arthur Figgis Surrey, UK