Figure 3.4: General Architecture of Task Computing Environment
3.4.1 Task Computing Architecture
Fig. 3.4 shows the TC architecture [81], which is composed of four different layers, performing complementary activities:
- Realization Layer: It is the bottommost layer, directly representing available facilities. There are three different types of entities at this layer: devices, applications and e-services over the Web.
- Service Layer: The available facilities from the Realization Layer are embodied into the form of service at this layer and services interfaces are constructed. Semantic Service Descriptions (SSD) comprising knowledge about these services are also created in order to disseminate information.
- Middleware Layer: This layer is in charge of service discovery, service composition and execution, and other management activities such as Service Publishing. In some way, it glues services created at the Service Layer with available underlaying technologies to support transport and management functions over them.
- Presentation Layer: It is considered to be the most important layer in the architecture. It provides the user with an abstraction of available tasks that can be performed in the environment, hiding underneath complexity, and allowing the user [to dynamically assemble components to perform the desired task.]
[81] Zhexuan Song, Yannis Labrou, and Ryusuke Masuoka; Dynamic service discovery
and management in Task Computing. In First Annual International Conference on
Mobile and Ubiquitous Systems: Networking and Services (MobiQuitous'04), pages
310-318, 2004.
|
2.3.1 Task Computing architecture
The Task Computing architecture is composed of four different layers, performing complementary activities:
- Realization layer: it is the bottommost layer, directly representing available facilities. There are three different types of entities at this layer: devices, applications and e-services over the Web.
- Service layer: available facilities from the Realization layer are embodied into the form of service at this layer and services interfaces are constructed. Semantic Service Descriptions (SSD) comprising knowledge about these services are also created in order to disseminate information.
- Middleware layer: this layer is in charge of service discovery, service composition and execution, and other management activities such as
[Seite 40]
Figure 2.8: Task Computing architecture. Source: [SLM04].
service publishing. In some way, it glues services created at the Service layer with available underlaying technologies to support transport and management functions over them.
- Presentation layer: it is considered the most important layer in the architecture. It provides the user with an abstraction of available tasks that can be performed in the environment, hiding underneath complexity, and allowing the user to dynamically assemble components to perform the desired task.
[SLM04] Zhexuan Song, Yannis Labrou, and Ryusuke Masuoka.
Dynamic service discovery and management in task
computing. In First Annual International Conference on
Mobile and Ubiquitous Systems: Networking and Services
(MobiQuitous’04), pages 310–318, 2004.
|
