Service Oriented Architecture. First and foremost in the presented architectural strategy is the need for a decoupling of individual elements in the architecture. No individual component should be bound to another component by means that makes it difficult to reprogram or exchange one of these components for another component. This calls for standardized methods of communication between the individual components in the system, regardless of software platforms. This will be achieved by employing a Service Oriented Architecture (SOA). In such a setup the development of services to expose data processing logic and data elements, using defined standards allows consuming clients to draw different types of functionality from different components and still retain the same method of communication. Several such standards exist (some of which is mentioned here): • SOAP (Simple Object Access Protocol) • JSON (JavaScript Simple Object Notation) • WMS (Web Mapping Services) • WFS (Web Feature Service) • WFS-T (Web Feature Service-Transactional) • SOS (Sensor Observation Service) • SES (Sensor Event Service) The above listed standards are all employed in different types of web services. The main point in using these service standards for communicating data and events between unrelated components is that all components will share the same standardized methods of communication. Components may be enhanced directly by consuming services already existing in other components. It ensures a loose coupling of services and components across different hard - and software platforms and thus mitigates the inherent complexities of constructing a complex system such as this. The below figure illustrates the principles, seen from the perspective of the WSMS: Figure 3.2.5 A schematic system overview from the perspective of the Work Site Management System (WSMS). In the above example all communication occurs through web service interfaces employing the above mentioned standards. The WSMS draws data from the relevant components. At the same time the WSMS exposes several different services that may be consumed by several different client applications. If for instance there is a need for showing some form of map window in another components client all mapping data can be drawn via OGC (Open GIS Consortium) compliant services (WMS,WFS) thus reusing already compiled data stores. In more detailed form this could be shown as follows: «serviceInterface» Interfaces::WebServ ice: EDMS CAD «flow» «flow» «flow» «flow» «flow» «ser...
