Standards

> geo service standards > WPS

OGC Web Processing Service (WPS) defines an interface so that clients can invoke any kind of process on a server. Relationship with the OGC coverage services, WCS and WCPS, is as follows.

  • WPS is a generic service where the processes to be invoked are only described syntactically (i.e., by function name and parameter types); the actual semantics is only provided in human-readable text. Both WCS and WCPS, on the other hand, have a well-defined semantics so that machine-to-machine communication becomes possible, including automatic finding and binding of service endpoints - in fact, many applications dynamically generate WCPS queries transparently.
  • WCS and in particular WCPS allow users to submit any kind of query at any time, while WPS only offers static functionality predefined by the service administrator.

That said, all these services complement each other in OGC's modular service landscape:

  • WCS allows simple, yet flexible data access;
  • WCPS allows versatile server-side processing and filtering of any-size coverages, expressible in queries: "any query, anytime";
  • WPS allows to "webify" any kind of application.

OGC document 09-045 defines how to use WPS as a carrier protocol for WCS and WCPS. We demonstrate such a WCPS / WPS integration with an example from Oil spill monitoring.