| 摘要 |
<p>It is disclosed a method for providing a context-based service to a terminal of a communication network, the method comprising, at a context server cooperating with the communication network: a) receiving a query from a service application suitable for implementing the context based service, the query indicating that the context server should perform an action when a query condition is fulfilled, the query condition referring to one or more attributes of derived context information indicative of a context of the terminal; b) generating a query evaluation trigger indicating that the query condition should be evaluated when the derived context information is updated; c) identifying raw context information allowing to derive the derived context information; d) generating a calculation trigger indicating that the derived context information should be calculated when an update of the raw context information is received from the terminal; e) receiving from the terminal an update of the raw context information and, according to the calculation trigger, calculating a new value of the derived context information according to the update; and f) according to the query evaluation trigger, evaluating the query condition by using the new value and, if the query condition is fulfilled, performing the action.</p> |
