The Context Manager (CM) component is a central element of the NetQoS system, which interacts both with the other components of the Monitoring and Measurement (MoMe) framework – specifically the MoMe Tool and the MoMe Manager – and with the two main repositories, namely the Ontology Repository and the Policy Repository. This interaction is needed in order to make the NetQoS system capable to dynamically react upon the detection of specific events related to changes in the overall execution context. Under this perspective, we can state that the CM helps the system become autonomic, since it provides it with the following properties:

• Automatic: this essentially means being able to self-control its internal functions and operations. An autonomic system must in fact be self-contained and able to operate without any external intervention
• Adaptive: an autonomic system must be able to change its operation. This allows the system to cope with temporal and spatial changes in its operational context
• Aware: an autonomic system must be able to monitor its operational context as well as its internal state in order to be able to assess if its current operation serves its purpose. Awareness controls adaptation of its operational behavior in response to situation or state changes.
  

We are designing the CM on the basis of a “Publish/Subscribe” paradigm: such element “produces” information to be used by the companion MoMe components. As an example, when a user launches an application, the CM has to notify the MoMe Manager of the occurrence of such event. At the same time, the CM also “consumes” information produced both by the repositories and by so-called “NetQoS-aware applications” (or, in the presence of NetQoS-unaware applications, by the Traffic Identification Engine which is also part of the NetQoS system).