Methods for estimating RRC state of mobile terminals in push servers

Push notification services send messages from servers in the cloud to applications on smartphones at any time to notify the applications or users of new or updated information. These services are characterized by frequent background traffic without user operations that affects the energy consumption of the mobile terminal and cellular network load. These factors are related to the RRC (radio resource control) state. If a server takes the RRC state of the mobile terminals into account and controls the timings for sending messages, the energy consumption and cellular network load can be reduced. In this paper, we propose methods for estimating the RRC state in push servers for controlling messaging timings. The evaluation result shows our method achieved an estimation accuracy of 70 % to 99 % depending on the server load for the estimation.