On 15/07/2014 13:52, Paul Corfield wrote:
On Tue, 15 Jul 2014 13:02:04 +0100, David Walters
wrote:

On Tue, 15 Jul 2014 11:46:52 +0100, Paul Corfield wrote:
[snip]

While I haven't expended a lot of brain power on the issue I can't see
how contactless bank cards can be checked by any railway inspector. On
a bus the inspector obtains a print out from the driver's machine and
checks card numbers presented by passengers against the list. Given
you just tap your bank card on a reader on the rail network and there
is no "write" record on the bank card (AFAIK) then what is there to
check? The transaction data all goes to a "black box" for calculation
of fares and caps.

It's possible I have a knowledge gap about the card technology and
cards can be checked in some way that I'm unaware of.


With contactless EMV cards (cEMV - bank cards) you are correct that
nothing can be written back to the card at the point of use (although
that may change in the future. So the only way that a mid-trip ticket
inspection can work is that the 'tap' record from teh inspector's device
is fed back to the back office system.

If there is a cirresponding 'entry tap' for the same card within an
appropriate interval before the inspection then all is well, and the
back office will charge thepassenger the 'normal' fare, subject to any
appropriate caps, discounts, etc. But if there isnt an entry tap, then
the passenger (or more accurately their card) can be charged a
'standard' (aka 'penalty') fare, although this may well require a change
to the Conditions of Carriage.

HTH

Kevin