In message , Dave Arquati
writes
Ian Jelf wrote:
I took a trip on a 38 from Piccadilly to Victoria yesterday afternoon.
Unusually, the conductor worked like a Trojan during the trip,
checking fares, calling out stops (with a lot of additional
information, too) as well as warnings. It was a pleasure to see.
My query, though, concerns Oyster.
I paid by Oyster Prepay and at Victoria I left the bus and went
straight into the Underground Station to top up it up. When I did
so, I was astonished to see my journey on the 38 already recorded on
my usage. How does this data get from the conductor's machine to
Oyster's "Central Control" so quickly?

Aha... the conductor's machine doesn't actually hold your information.
The information is stored on the card itself, so when the conductor
marks a bus journey using his machine, that bus journey is stored on
the card. As soon as your card then comes into contact with the central
network (mainly via LU gates, ticket machines or validators) then that
information can be synchronised with the network.

At least that's how I understand it works.

D'oh, I suppose that that should have been obvious! :-)) Thanks for
telling me, though.
--
Ian Jelf, MITG
Birmingham, UK

Registered Blue Badge Tourist Guide for London and the Heart of England
http://www.bluebadge.demon.co.uk