The service stack (Figure 2) consists of the WCPS interface implemented by a Java servlet, the rasdaman array server middleware, and a relational DBMS holding the raster data. The Java servlet accepts WCPS requests adhering to the WCPS XML schema specification, and returns the responses. Coverage results consist of an XML document accompanied by binary coverage data in the requested encoding format,encapsulated within a multipart/mixed HTTP response. This format allows on principle even a web browser to be used as a client, by uploading an XML request directly
to the web service. Non-coverage results can be shipped back directly within the XML response.