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Data for Routing
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RouteWare products have already been used with data from the following major worldwide street-data suppliers:
- AND (World wide, scale 1:300,000)
- DMTI Spatial (Canada, detailed)
- Europa Technologies (World wide, scale 1:1,000,000)
- EuroGlobalMap (Europe, free, scale 1:1,000,000)
- GeoBase (Canada, detailed, free, not fully attributed)
- LeadDog (Worldwide)
- HERE (former NavTeq) (Globally, detailed)
- Ordnance Survey, ITN (UK data, detailed)
- Ordnance Survey, OpenData (UK data, free, scale 1:25,000)
- TomTom MultiNet (Globally, detailed)
Many resellers for RouteWare products can also help you find street databases appropriate for your task. Some may also be able to quote better
prices than when you buy direct from the vendors above.
OpenStreetMap (OSM)
OSM is free data for the whole World. Coverage and quality can be very different.
You may be lucky that quality is acceptable in your project area and for your purpose,
but don't count on it. Some areas are high quality and full coverage, while others miss a lot.
TIGER/Line
TIGER data is free data for USA. Please read this special section on TIGER.
OpenRoad
Some of the best free data around and for the UK. See our download section.
Your own data
The data mentioned above all have a topologically correct structure, which means they are almost ready for use.
But what should your own street data look like, if it is to be used in RouteWare products? The short answer is
they should snap and split at intersections and the network should be plane unless there is an overpass.
Here are some examples of networks which are NOT correct, but which look right unless you check out the details:
Example 1: Missing snap at an intersection
This means the network does not connect and movement to / from the disconnected section is not possible.
In the example below, the gap is just 1 meter and cannot be seen at normal zoom levels.
Example 2: Split at overpass / underpass
This means a lot of impossible turn movements are suddenly made possible.
This is a typical problem with TIGER data.
Example 3: Does not split/break at intersections
This means turns are not possible at most intersections.
Example 4: Double digitization with two street names, here name + route number
Not a really big problem, but the result of a route calculation may include one of the two streets
in a more or less random fashion.
Example 5: Multi sectioned polylines
Polylines with more than 1 section are ignored. They will not be part of any route.
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