On Thu, 26 Nov 2009 13:16:08 -0800 (PST), MIG
wrote:

But it's that assumption of guilt again, that you don't get with a
paper travelcard, ie you are assumed to have gone beyond your zones
unless you can prove that you didn't.

That's the basis for most such smartcard schemes - charge the maximum
possible on entry, refund back on exit.

What it means is that anyone in the system (provided they don't go
past the boundary of its validity) always has a valid ticket provided
they've touched in.

Neil

--
Neil Williams
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