Streaming Data Services (WMS, WFS, etc.)
The Open Geospatial Consortium (OGC) has defined several REST protocols for the transfer of geospatial data from servers to client applications, summarized below. For each of these, by using a specially structured https request, you can call a dataset (eg. orthoimagery, boundaries, highways) into your GIS software application.
- WMS - Web Mapping Service. Delivers georeferenced map images (e.g. GIF, JPG) without storing a local copy of the dataset. May also contain a Styled Layer Descriptor (SLD) to specify symbolization. Works great for orthoimagery and basemap reference data.
- WMTS - Web Map Tile Service. Delivers pregenerated georeferenced map images and may contain styles, dimensions, or tiling schemes to specify the display settings.
- WFS - Web Feature Service. Serves, queries, and updates feature geometry and attributes using a Geography Markup Language (GML) profile.
- WCS - Delivers raster data and cell values, such as elevation values from a digital elevation model (DEM) or pixel values from a multiband image.
Recommended Services and Directories
- Raleigh - https://maps.raleighnc.gov/arcgis/rest/services
- Wake County - https://maps.wakegov.com/arcgis/rest/services
- NC OneMap - https://services.nconemap.gov/secure/rest/services Many North Carolina statewide feature and orthoimagery layers
- NC Dept. of Transportation - https://gis11.services.ncdot.gov/arcgis/rest/services/
- NC Emergency Management - https://spartagis.ncem.org/arcgis/rest/services/Public
- USGS Data - US List
Links for numerous services, including: Orthoimagery (High Resolution, NAIP), Elevation (NED), Land Cover
- geoseer.net - Global Catalog
Indexed hundreds of thousands of live servers with nearly two million layers.
- ArcGIS.com - Global Catalog
- Esri's clearinghouse for map services. Services get added to this index from user contributions.
- geo.data.gov - US Catalog
Data originates primarily from government and academic sources. Click Advanced Search Options, and then check the box for "Live Data and Maps" specify "WMS" as the keyword. In the search results, go into the details of any WMS service entry and find the WMS URL under "Service Availability"
- mappingsupport.com - US List
Catalog of over 3,500 ArcGIS servers, among other things.
To connect to a service, select and copy a service link and paste the link where your software asks to specify the URL. If the service is coming from an ArcGIS Server (most are), then the connection will work best by choosing ArcGIS Map Server or Feature Server in your software, rather than WMS, WFS, etc.
You can find more detailed instructions by searching online, or use one of these links: