Fares belong to multiple networks

[miklcct]

Describe the problem

I am trying to model London transport fares. However, for the purpose of fares, different fare products have different interpretation of the network. For example, using an Underground ticket, the network contains only Underground and DLR routes. Using a National Rail ticket, the network contains only National Rail routes. Using a contactless payment card, the network contains both National Rail and Underground, DLR routes where they can be joined together as a single fare leg.

Use cases

To model different fares used for different, overlapping network within a region.

Proposed solution

relax the requirement in route_networks.txt to allow a route to be assigned in multiple networks.

Additional information

No response

[tzujenchanmbd]

Previous discussion for reference: #389, #405

[felixguendling]

What you describe would not require a mapping from one route to several networks. It can be done using fare_transfer_rules.txt.

Networks:

• A (here: National Rail)
• B (here: Underground)

Tickets:

• A
• B
• AB (here: contactless)

Fare Rules (multiple rules apply to each A and B!):

• network=A -> regular A ticket
• network=B -> regular B ticket
• network=A -> contactless AB ticket, fare_leg_group_id=AB
• network=B -> contactless AB ticket, fare_leg_group_id=AB

One Fare Transfer to allow using AB ticket for AB:

• from_leg_group=AB
• to_leg_group=AB
• fare_transfer_type=0
• (no transfer product)

[miklcct]

What you describe would not require a mapping from one route to several networks. It can be done using fare_transfer_rules.txt.

Networks:

• A (here: National Rail)
• B (here: Underground)

Tickets:

• A
• B
• AB (here: contactless)

Fare Rules (multiple rules apply to each A and B!):

• network=A -> regular A ticket
• network=B -> regular B ticket
• network=A -> contactless AB ticket, fare_leg_group_id=AB
• network=B -> contactless AB ticket, fare_leg_group_id=AB

One Fare Transfer to allow using AB ticket for AB:

• from_leg_group=AB
• to_leg_group=AB
• fare_transfer_type=0
• (no transfer product)

Sorry, your modelling does not work here.
If my journey is from X to Y on network A then Y to Z on network B with integrated fare, the fare charged needs to be a contactless X to Z fare for use of both networks. Your modelling implies that the second leg is completely free when fare_transfer_type = 0 and no transfer product.

Also, there isn't a "contactless AB ticket" here. The fares are defined on a point-to-point basis and, as such, it cannot be modelled as transfers as the system doesn't care where you change trains (except very limited situations where the system does care).

[laurentg]

For the record, we also have one example at hand of a fare system where relaxing the uniqueness of network per route restriction would help, of which we (Mecatran) are the data producer.

Also the way the tables are modeled (having a dedicated route_networks.txt relation table, making a N-N relationship possible, on top of the other route.txt::network_id), wrongly suggest that a N-N relationship is possible, and is rather misleading.

In summary: strongly in favor of this proposal.