Inputs and Behaviors

When invoking GetMap a WMS query can specify:

Input Required Description
VERSION=version Yes Request version. Spectrumâ„¢ Technology Platform WMS supports both version 1.1.1 and 1.3.0 of the OGC specification.
SERVICE=WMS Yes Service type. This is always WMS.
REQUEST=GetMap Yes Request name. For a GetMap request this is always GetMap.
LAYERS=layer_list Yes

The layer or layers to be included in the map image. Each layer should be separated by a comma. For example:


STYLES=style_list Yes

Comma-separated list of one rendering style per requested layer. A style is required for each layer requested. If no style is requested, the attribute must be present but without a value. If requesting multiple layers, the styles listed should be in the same order as the layers. For example:


In the above example the second style (for the second layer requested) is left blank, allowing the default style defined for the layer to be used.

SRS=namespace:identifier Yes for 1.1.1 The spatial reference system used in the map (numeric representation of the projection of the map, also known as the coordinate reference system). This parameter is only used for 1.1.1 versions of the OGC specification.
CRS=namespace:identifier Yes for 1.3.0 The coordinate reference system used in the map (numeric representation of the projection of the map, also known as the spatial reference system). This parameter is only used for 1.3.0 versions of the OGC specification.
BBOX=minx,miny,maxx,maxy Yes The area to be mapped. The bounding box is specified as the four coordinates of the corners of the box that bounds the map area to be included in the image. The BBOX coordinates are always expressed in the units of the SRS or CRS. The axis order (which axis is x and which axis is y) is determined by the authority that owns the coordinate system definition. This is most frequently EPSG, whose definitions are available at For the GetMap operation, you need to be aware of the axis order for each coordinate system when you construct the BBOX.
WIDTH=output_width Yes Width in pixels of map image.
HEIGHT=output_height Yes Height in pixels of map image.
FORMAT=output_format Yes The format in which the map image is to be returned.
TRANSPARENT=TRUE|FALSE No The transparency and color of the background of the image. If nothing is specified, the value is FALSE.
BGCOLOR=color_value No Hexadecimal red-green-blue color value for the background color (default=0xFFFFFF).
RESOLUTION=resolution No The DPI of the map image. If less than 72 dpi, an exception is thrown.
EXCEPTIONS=exception_format No The format in which exceptions are to be reported by the WMS (default=XML).

The request parameters are always sent as an HTTP query string. The following are sample GetMap requests:

WMS version 1.1.1:


WMS version 1.3:

Note: The code above should all be on a single line with no breaks. Due to space limitations, we cannot display the request in such a way in this document.