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Figure 1: The KOMET Architecture (Click the image to enlarge it) |
The KOMET Architecture is built up from three subsystems (see figure 1):
Most of today's complex applications, such as SAP ERP, PTV logistics platform and many others are implemented in stacked layers (tiers). Communication between these layers is organised with help of well defined and documented interfaces. In general, three layers are being designed. Thus, this kind of software architecture is referred to as three tier architecture. The basic layer is the data tier, typically realised as a central data base with help of a Relational Data Base Management System (RDBMS). The application tier resides in the middle and provides the functionality of the whole software system. The last layer is the presentation tier, which is responsible for user interaction. It's very common to realise a graphical user interface (GUI) for this purposes.
The structure of the KOMET Architecture is similar to this three layered outline. The data subsystem referres to the data tier, the model subsystem to the application tier and the dialogue subsystem corresponds to the presentation tier. A fouth element, the EUS kernel mediates between these subsystems and provides the interfaces between the layers this way.
A basic principle in many engineering disciplines that complex structures are assembled by by plugging simple building blocks was transferred to software technology by means of component oriented software development. The idea behind this software development paradigm is to build Software systems based upon resusable software comonents. Component technologies provide the technical foundation for implementation of components. Thus, software componentes are able to communicate with each other and it is possible to use them independently by third parties. Components can be plugged, and unplugged in a system at run-time. This enables the design and implementation of dynamic software systems which can be easily adapted to specific needs just by plugging the appropriate components.
The application tier is realised with help of such software components. The functinality of the whole software system is implemented as the composition of collaborating problem solving components (solvers). The planning application residing in the presentation tier is realises as a software component. The only difference to a solver is that it provides a graphical user interface to interact with the user. Java's remote method invocation (RMI) serves as the component technology within the KOMET Architecture.
If a function is provided as a service, the service consumer will send a service request to the service provider. The service request is processed and an appropriate service response is sent back to the consumer. The Extendsible Markup Language (XML) shows a special strength in terms of definition of exchange of virtually any type of information in heterogenious environments. Thus, it would stand to reason to define service request messages as well as service response messages with help of an XML instance.
The KOMET Architecture defines an interface based on XML messages for all of the provided services. All communication between the components and the DSS kernel as well as between different components is realised with help of service requests and service responses.
Such concepts are referred to as Service Oriented Architecture (SOA) or Software as a Service (SaaS).
Martin Döllerer
- zuletzt geändert am 01.01.1970 um 01:00 Uhr