Operational Review #3
Yes, Demis is OpenGIS WMS 1.1.1 compliant. The help link for the Demis software goes to http://www.demis.nl/home/pages/wms/docs/intro.htm which mentions that it uses OpenGIS WMS. The page at http://www.demis.nl/home/pages/wms/demiswms.htm certifies that version 4.0 (we have 4.0.5) is WMS 1.1.1 compliant. Here's my answers:
- Describe in a sentence or two your overall operational experience related to WMS. (e.g., scientific visualization; geospatial visualization, etc). What kinds of WMS servers and/or clients do you have experience with? (e.g., commercial products, open source, or independent implementations, please provide as much detail as possible).
- Answer: We use OpenGIS WMS 1.1.1 compliant software called Demis Map Server for displaying a world map annotated with dots for cities on our cities web page (http://eol.jsc.nasa.gov/cities/map/). It is used solely to aid users to find cities of interest by using panning and zooming of the maps. Information on the commercial WMS Demis product can be found at http://www.demis.nl/home/pages/wms/demiswms.htm . We are also using the software to provide zooming and panning of an image of Mt. Everest.
- What types of applications do you use WMS servers/clients for? Are they suitable for your applications? (e.g., Do they work well with the data types and data manipulations in your application?)
- Why do you choose to use WMS over other protocols for your applications?
- Answer: The WMS applications we use are described in the answer to question 1. When they are functioning, they work well. Sometimes they stop working and diagnosing the problem is vague. For example, one of the servers maps stopped working one day. I found nothing wrong in the setup. Then it spontaneously started working again a few days later. This, however, may be more an issue related to the application software than the OpenGIS standard. We chose Demis Map Server over others because it outperformed the others in terms of speed and another organization doing related work to ours was using it for mapping reefs.
- Are the WMS systems easy to use? (e.g., Is it hard to learn how to use WMS systems?)
- Answer: The software we use is not easy to use. It is either embedded in ASP or Flash and the only way we've been able to use it is by modifying the manufacturer's sample code.
- Does the performance of the WMS systems you have experienced meet your requirements? (e.g., Does it take a long time to access/ view data in WMS systems?)
- Answer: The performance (load times for the maps) is very good.
- What operational challenges do the WMS systems present? (e.g., Does it require advanced processing power, large amounts of memory, complex configuration, etc.? Are the systems easy to deploy and maintain?)
- Answer: See the answer to questions 2 and 4 for the operational challenges and ease of deploy and maintenance. There has been no noticeable large processor power requirements.
- How well do the WMS systems scale to large numbers of simultaneous users, or to large datasets?
- Answer: The one we use works fine under heavy loads.
- Can you provide information on user statistics of your WMS systems?
- Answer: We keep web logs for a couple months, which can be parsed if needed to provide statistics on WMS map usage.