Web Map Service
----- Original Message -----
Sent: Thursday, May 16, 2002 10:52 AM
Subject: Re: New Catalog XML Draft
> # John Caron wrote:
> # > c.. add new
service types: (DODS | ADDE | NetCDF | Catalog | FTP
> | OpenGIS | WSDL | Other)
> I agree that instead of OpenGIS you need explicit WMS, WFS,
> Joe Wielgosz writes:
> # How much effort should
THREDDS put into supporting particular data
> # provider site
> # [...]
> # If you look at different data providers
websites, they all have their
> # own way of mapping datasets,
collections and access methods to URLS, and
> # some are quite complex.
They might use any combination of different base
> # URLs, subpaths or
suffixes, CGI parameters, or who knows what else.
> The OpenGIS
services (e.g., Web Map Service--WMS) list a URL prefix for
operation supported by a particular machine. The prefix includes
hostname and, as needed, port number, path, and some CGI parameters.
The entire prefix is just an opaque string. Then, the specification
what parameters are to be added to the prefix in order to
> construct a
valid request for each operation.
> Examples for WMS:
> URL prefix:
> Complete URL to request service metadata:
> Complete URL to request a particular map:
> In the last example showing the GetMap request, most of the
> are variable. I'm not sure whether in the THREDDS catalog it
> to include only the URL prefix and let the client form a valid
> request, or include one of the possible complete GetMap URLs so
> all clients can at least retrieve something while WMS-aware
> can modify the URL. Probably the second, more helpful option is
> in this context.
> -Jeff DLB, WMS 1.1
Thanks for the concrete example (nice picture, too!). A few
Can one figure out all the possible parameter values from the
Does the WMS spec allow the client to specify the projection
In the specific example above of the topo map, can the client
specify/discover what the false color mapping is?
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