[RouterGeocoder] Routing Data Schema

[Stephen Woodbridge]

Daniel Kastl wrote:
> Hi Steve
> 
> First of all, thanks a lot for starting something really practical on
> this list. Hope you had some hours of sleep left.

>> Questions, Concerns, Issues, Missing information?

> Without going very much into details (it's already late here), my first
> thought reading your schema was: do we want to see OpenRouter as a
> vehicle navigation library, or do we see it more general as a library
> for network analysis?
> With pgRouting we tried to keep it open to any kind of network, and I
> heard for example about someone using it for fire prediction. Another
> request recently was about nautical navigation. And I think there are a
> lot of networks, which we're not so much aware of.

I have no objections to supporting general network analysis. As you say 
our primary use case is vehicle routing. Some useful variants to that 
are things like:

Chinese postman - IIRC which is useful for planning snow plow routes
Minimum Spanning tree - for Cable/Telephone/Fiber installation
Isochrons - for drive time analysis
Traveling Sales Man - for package delivery and pickup from a depot

And yes there are a lot of other industries that need network analysis. 
I have no intention of excluding them, but I have not the expertise to 
include them either.

> This said, I know that the main use case is vehicle navigation, and it's
> the best example for a demonstration and to explain to non-experts.
> 
> I think you're an expert in Navteq data, Steve. And I'm sure the Navteq
> model isn't a bad one. I probably would have studied about it more if

Navteq has a complete model. It is very normalized and sometimes a pain 
to deal with. TeleAtlas also has a good model but I'm less familiar with 
that.

With respect to Navteq, go to the http://www.navteq.com/ and follow the 
links to the developers section. Sign up as a developer (costs nothing) 
and you can download specs and sample data.

> they had data available for Japan. So comparing different data sources
> is a good idea. I don't think that the OpenStreetMap model is a good one
> for routing purpose.

Yes I would agree with this. We can hope that with input from us and 
others that it will improve over time.

> So my question is: do we see the main purpose of OpenRouter in road
> navigation? Or do we want a library for spatial network analysis, where
> "Shortest Path" search is one core algorithm and vehicle routing is just
> a popular use case.
> 
> I'm more in favor of the latter. But I agree that we need to primarily
> support vehicle routing data.

I'm happy with either, but I think we should focus on our areas of 
strength and expertise. I would like to see us do an outreach for other 
use cases and to have experts in these discuss the direction we are 
going and what changes we need to better support them.

My concern is that if we try to be all things to all people -- we will 
end up being nothing useful for anyone. We should work from our areas of 
core competence and strength.

Which gets me back to my questions :) How does this proposal look with 
respect to:

1) vehicle routing problems? What is missing that we might need?
2) spatial network analysis? What is missing that we might need?

How would it work with say pgRouting?
If we had a successor to pgRouting, what features would we like to 
support that might not be represented in this model?

> Hope this made some sense,
> 
> Daniel
> 
>