Web services are a means of streaming GIS data to your computer without having to download the data in order to use it. Using web services avoids the need to download data which can be very large and avoids the problem of not knowing if you are using the most recent dataset.

Types of Services

Esri Format

  • Recommended for best performance and ease of use when using ArcGIS products
  • Symbology already defined
  • Used by web-based applications that you develop using Esri application programming interfaces (APIs) such as Javascript

OGC Format

  • The Open Geospatial Consortium (OGC) format can be used by ArcGIS Desktop but with one exception the OGC format is generally most useful with non-Esri software
  • The format types supported by the GIS Hub are:
    • Web Feature Service (WFS) – streams “raw” vector data (e.g., roads, rivers), layers can be turned on/off, and symbology can be changed by the user. Use this with ArcGIS Desktop if you wish to define your own vector data symbology. It is highly recommended to zoom in to area of interest before loading this data due to performance
    • Web Coverage Service (WCS) – streams “raw” raster data (e.g., aerial photography), layers can be turned on/off, properties can be changed by the user. Use this with ArcGIS Desktop if you wish to set adjust the display properties of raster data. Performance is very good with ArcGIS Desktop and is very useful if the Internet connection is slow.
    • Web Map Service (WMS) – streams an image of vector and raster data, view only, layers can be turned on/off. When using ArcGIS Desktop, it is generally better to use the Esri format rather than WMS to ensure maximum capabilities.
    • Web Map Tile Service (WMTS) - streams pre-built image tiles depicting vector and/or raster data.  When using ArcGIS Desktop, it is generally better to use the Esri format rather than WMS to ensure maximum capabilities.
    • Keyhole Markup Language (KML) – streams an image of vector and raster data, view only, layers can be turned on/off

Organization of Services

The North Dakota GIS Hub REST (Representation State Transfer) interface is used to browse and review the capabilities of individual web services. Each web service has associated with it one or more capabilities. For example, some include WMS and WCS, others have only WFS and KML. All have the capability to work with ArcGIS. The following shows the general rule of thumb:

Capabilities Type Service Coordinate System
WMS, WCS All_* Web Mercator Auxilliary Sphere
WFS, KML Features/* WGS84
WMTS Basemap_* Web Mercator Auxilliary Sphere

How to Find the Services

  • The Hub Data Portal is the way to search for or browse for web services
  • Searching for web services can be simply done by entering in a search word such as "roads"
  • The results from searching for or browsing will display data titles, click on the title of interest
  • Click on the "Go to Resource" button associated with the resource containing "Web Services" in the name

How to Use the Services

ArcGIS Desktop Software

Esri Format Steps

  1. Open up ArcMap/ArcCatalog
  2. Click on GIS Servers
  3. Click on Add ArcGIS Server
  4. Leave the default Use GIS Services as the default and click Next
  5. Enter the server URL: "http://ndgishub.nd.gov/arcgis/services" (don't enter the quotes)
  6. Click the Finish button
  7. More information is in the Esri help

WFS Steps

  1. Please visit Esri help
  2. Be sure that you have installed the Data Interoperability extension.  Note that this extension is downloaded from the Esri software download site, you do not need to purchase the extension for use with just WFS.
  3. In ArcCatalog you should see an Interoperability Connections option at the same level as Database Connections, GIS Servers, etc. Expand the Interoperability Connections item
  4. Double-click on Add Interoperability Connection
  5. For the format, select WFS (Web Feature Service)
  6. Click on the Parameters button
  7. Determine the URL of the server and name of service to use, follow these steps:
  8. Paste this into the URL field and then for the Feature Types field, click on the ellipsis button (three dots). Select one or more of the layers then click OK.

WCS Steps

  1. Please visit Esri help
  2. Determine the URL of the server and service to use, follow these steps:
  3. Paste this into the URL field and then click on the Get Coverages button

WMS Steps

  1. Please visit Esri help
  2. Determine the URL of the server and service to use, follow these steps:
  3. Paste this into the URL field and then click on the Get Layers button

WMTS Steps

  1. Please visit Esri help
  2. Determine the URL of the server and service to use, follow these steps:
  3. Paste this into the URL field and then click on the Get Layers button

Non-ArcGIS Desktop Software

GIS desktop software such as Gaia, QGIS, and gvSIG can utilize the GIS Hub OGC web services.  The usage of the web service URLs is generally the same as that for the ArcGIS Desktop software.