Haiti cascading WMS deployed - single WMS access point for Google Earth, OSM, Gaia
(Updated April 2010) CubeWerx and The Carbon Project have deployed a Cascading Web Map Service (WMS) as part of the growing open information network for the nation of Haiti. The service is being posted on CrisisCommons.org and may be accessed now in Google Earth (Image overlay), Gaia, OpenStreetMap (OSM) editors and other applications with this WMS service link-
The Haiti SDI Cascading WMS is offered by CubeWerx as a free public resource to help support relief, rebuilding, communications and data update operations. The practical benefit is to provide a simple, single access point (above) for applications like Gaia, Google Earth and OpenStreetMap editors by “cascading” online WMS. WMS are currently being cascaded from New York Public Library, University of Cincinnati, Calit2, Haiti.opensgi.net, CubeWerx and others, as well as imagery from GeoEye and DigitalGlobe on a variety of WMS - and any organization is invited to contribute WMS URLs to support Haiti relief. The Haiti SDI Cascading WMS can combined with the Haiti OSM WFS and UN WFS to get a clear picture of the environment using applications like Gaia at the following URLs -
Haiti SDI OSM WFS
Haiti SDI UN WFS
The technical benefits of a cascading WMS are -
1. It can connect to all official WMS versions and most unofficial ones - so your application doesn't have to know all the different protocols. For example, if your client supports WMS 1.1.1 and you use a cascading WMS you can connect to 1.0.0, 1.1.0, 1.3.0-only servers.
2. The cascading WMS supports many image formats and will convert the data to your desired format. So if an OSM client wants the image in PNG using a cascading WMS you can connect to servers that only serve either GIF, PNG, TIFF, JPEG, etc.
3. The cascading WMS supports a large number of coordinate systems and will convert the data to your desired coordinate system. Your client wants the image in Geographic and using a cascading WMS you can connect to servers that serve only UTM, Mercator, etc.
4. The cascading WMS supports loop detection. When retrieving the capabilities of all the remote WMSs it will not go into an endless loop. Server A can cascade Server B and Server B can cascade Server C and Server C can cascade Server A. Your client can connect to any of these servers and get an aggregated capabilities of all the servers.
Interesting to note that CubeWerx's CubeSERV is the only cascading WMS - that implements all the functions above (as far as I'm aware). The Haiti Spatial Data Infrastructure (Haiti SDI) is a public resource that may be used in Google Earth, OpenStreetMap, the Gaia SDI Platform and other applications to support relief, rebuilding, communications and mapping data production. The Haiti SDI is based on international standards for Web Mapping Services (WMS) and Web Feature Services (WFS) from OGC, and any organization is invited to contribute.