Continuous Adaptation

For some applications it is important to be able to react to changes of the resources in order to provide a reasonable service even with low resources. For instance, multimedia applications which use unreliable connections, e.g. wireless communication, Internet, must modify the representation of data according to the conditions of the network in order to deliver usable results. Changes of the resource conditions may occur without following a certain pattern or any other regularity. The modification of the application is done by tuning of parameters. Such modifications are here denoted as continuous adaptation . The triggers for the continuous adaptation are not discrete events as for dynamic adaptation, but continuously changing conditions of resources.

 

Figure: Continuous adaptation  

For continuous adaptation the resources are monitored and the adaptation process initiated as the resource conditions change. The result of the continuous adaptation is the modification of parameters (s. figure ).

Though static adaptation and continuous adaptation differ concerning the objective and in the realization they share some problems with dynamic adaptation and will therefore be evaluated in this chapter. For the evaluation a list of requirements is specified in the following section.