The invention relates to apparatuses, a method, computer programs and computer-readable media for controlling mode change from a normal cellular communication mode to a machine-to-machine or device-to-device communication mode and to ensure sequence number synchronization between a sender and receiver ends when said mode change is performed. The mode change control is performed by controlling the duration of the transition period for switching from the cellular communication mode to the machine-to-machine or device-to-device mode and by using a temporary server for transmission of a desired data flow or by sending at least one dummy packet.