The talk page on the network key has this question. It has not answered since 11 September 2023
There has been no concensus on how we should put values to network=* on public transport routes in Hong Kong and there is a controversial discussion ongoing. What is the definition of a network=* where the routes should be tagged the same value? -Miklcct (talk) 13:33, 11 September 2023 (UTC)
A similar discussion has started in the OSM Israel Telegram channel (in Hebrew).
I guess mappers in the US can automatically place the local transit authority as the network.
However, for mappers elsewhere in the world, it is not clear what makes a network, how does the network relate to the operator, etc.
In the case of Athens, Greece, the public transport network consists of several networks operated by various operators, all merged into one big network for better co-ordination.
Specifically, there’s a separate network for the subway, separate for the tram, separate for the buses, separate for the electrified buses, etc…
So, I assume the network key refers to that specific network, that is for example the subway lines operated in an area (because usually in many cities there are several operators who run the subway lines and not just one).
What you describe is more akin to operator=*. Again with Athens as an example, most lines are operated by ΟΣΥ, a subsidiary of OASA, and some are run by private operators (KTEL Korinthias, Thivas etc.), but always under OASA branding and ticketing.
Not necessarily: the MVV in Munich, Germany does not operate any vehicles.
It’s a public owned company (Ltd, GmbH or whatever legal form), owned by the counties that participate/co-operate in that topic. And the MVV takes care of the tenders for operation, tickets, public funding/subventions, …
The problem with it is that it differs from country to country, operator to operator and from mapper to mapper.
Here in Germany, a PT “network” typically refers to a Verkehrsverbund (traffic association). This is because they typically are in charge of the pricing and timetables but usually don’t run their own vehicles, instead preferring to contract them out onto others or are a collection of multiple, more or less independent operators (a Verbund is some sort of group, unity or federation).
Exceptions are when PT is operated independently with its own pricing scheme. Long distance trains in Germany fall under this, they’re outside the realm of traffic associations and all the pricing etc. are handled by the operators themselves (which is why it’s typically to see the network being the same as the operator for these services).
But note that this isn’t universal and a network can also refer to individual modes.
For example, Seattle (mappers) distinguishes the individual railways (streetcars, Link and Sounder) even if they all are part of Sound Transit (but not operated by them — Sounder e.g. is run by BNSF). No idea how busses are governed, though (i.e. whether it’s on a per-county basis or by Sound Transit altogether).
MTA railways in New York are similar in that OSM distinguishes between Metro North and LIRR and use generally identical fares but with the occasional difference (e.g. school and group tickets), not to mention you can’t pay for an MNRR ride with an LIRR ticket unless you buy a shared ticket. MTA also handles fares of busses and the Subway which apparently use the same pricing (you can correct me) but the individual routes are once again are distinguished on OSM (the former tagged as NYC Transit, the latter as NYC Subway, though the latter is a subsidiary of the former if I read it correctly).
Now, which one is better is difficult for me to judge (for now) so I refrain from any opinion on which one is ultimately better.
It seems that in Israel, the Ministry of Transportation is the network. It performs all above mentioned roles.
The following are fully assumed by the ministry:
defines where and when buses, trains, … will circulate, where they will stop
publish invitations to tender for operation (buses, trains, …)
define which fares have to be paid by passengers (fare-zones, …)
which ticket types are available
The operational aspects of the network were delegated to private service providers. For example:
The ministry has an open GTFS system that is used by several private service providers.
Several alternatives, physical and digital, are implementing the fare system.
There are several operators that are licensed by the ministry to operate specific bus routes, while other operators operate other means of transportation, including trains, light-rail, and shared-taxi.
Maybe it is more useful to differentiate in this way:
network is a rider facing name. It is reasonable to expect riders know what network they use, what tickets they need to buy, if they are compatible etc.
There are maps of the network that are intended for public consumption.
operator is not. You don’t need to know which specific company the government has sold the rights to the transit network to, or whether the government runs it themselves, or which companies run which portions of the network.
There can be some debate when there is one broader transit agency that runs multiple modes.
In London, the London Underground can be regarded as a separate network, the Overground the same, London Buses another. Each has many different operators, and all fall under the umbrella of TfL (Transport For London). It is not wrong to refer to the bus network of any given city as such, but what name should be in network=* (the bus network’s or the broader one) is up for debate.
In the case of Israel, this is not more useful. One can buy tickets for the same ride from several vendors. All these vendors need to comply with the fee rules set by the Ministry of Transportation.