Asynchronous Communication Information Access

24 Copyright © 2011 Open Geospatial Consortium to be analyzed first, which might be a time consuming task. The latter can be due to the fact that the asset – for example a reconnaissance drone or satellite – is not located above the area of interest and therefore has to be moved there, first. Another example is to have the service itself inform the client about a situation of interest. In either case, this shows that the SPS needs to have functionality to support an asynchronous interaction pattern.

6.7 Information Access

The service functionality of SPS does not encompass operations for direct access to the information gathered or produced by an asset. Data retrieval services like SOS Sensor Observation Service, WMS Web Map Service, or WCS Web Coverage Service, or even FTP or REST-based services are much more suited to perform this functionality. The SPS interface provides references to the information gathered by an asset. The reference data contains enough information to retrieve the complete set of data output by an asset for a certain task. Copyright © 2011 Open Geospatial Consortium 25 7 Sensor Planning Service – Implementation Model

7.1 Interface Overview

The SPS operations can be divided into informational and functional operations. The informational operations include GetCapabilities, DescribeTasking, DescribeResultAccess , GetTask and GetStatus operation. The functional operations are the GetFeasibility, Reserve, Confirm, Submit, Update and Cancel operations. All functional operations have an effect on the asset management system. The SPS defines five interfaces with eleven operations that can be requested by a client and performed by an SPS server. In addition, it incorporates two interfaces from the SWE Common Service Model [OGC 09-001] – these interfaces define two more operations. Figure 11 is a UML diagram showing these interfaces grey interfaces are defined by OGC 09-001. 26 Co Figure 11 — SPS interfaces UML diagram NOTE In this UML diagram, the request and response for each operation is shown as a single parameter that is a data structure containing multiple lower-level parameters. These structures are discussed in subsequent clauses. The UML classes modeling these data structures are included in the following clauses. pyright © 2011 Open Geospatial Consortium