On Mon, 12 Jan 2009 09:21:06 -0800 (PST), Mizter T
wrote:

On 12 Jan, 16:32, MIG wrote:

If the Putneys became an outerchange, it was raise the old question of
whether touching along the way can override the route assumed by
Oyster between the start and end points (if that was different). *That
is, while adjusting to treat two journeys as one continuation, could
it then still use the data about the two journeys to know that the end
to end journey wasn't by a different route?


Indeed - a very good question that.

[snip]

I understand the theory is that all origination and destination
stations (i.e. pairs of stations) have a fare set for journeys between
them. The basic question, as you say, is whether that can be
overridden according to things that happen en-route - i.e.
outerchanges passed through.

This whole subject probably deserves a thread of its own on utl, so
perhaps I'll start one in the near future - there's enough other stuff
going on now to deal with (for my pea brained head at least!).

Oyster can only deal with one PAYG fare between an origin and
destination at present. There is a further project underway to support
extension of PAYG to NR which will introduce the concept of intermediate
validation to confirm a route and also for more than one rate between
origin and destination pairs to be held. The last I heard was that
LUL would be using intermediate validation to allow people to travel via
non Z1 routes and for them to benefit from that - provided they validate
at the designated intermediate point (almost certainly the natural or
logical interchange route - e.g. Rayners Lane station for some west
London trips by tube). There is not yet sufficient clarity as to
whether the train companies will use the intermediate validation concept
(or more accurately I haven't read anything definitive about it).

One other aspect of the project is that leaving the LU system (e.g. at a
NR terminal station like Victoria) and then entering the NR side would
automatically extend permissible journey times to reflect the fact that
many more trips (valid via PAYG) will take longer than the 2 hour
journey time "cap".

--
Paul C