Abstract: In a communication system (SYS) in which a packet data transfer is performed between the network side (NS) and the subscriber terminal side (SS) a physical connection (LC) is maintained during the data packet transfer. An active period detector (AP-DET) detects an active period of data packet generation by evaluating the inter-arrival time (TDIFF) between successively arriving data packets (DP). If the inter-arrival time (TDIFF) falls within a predetermined range a physical connection maintaining device (LC-MAIN) maintains the physical connection (LC) even if a transmitter queue (TR-QUE) temporarily becomes empty. Therefore, within the active period (AP) the transmitter (NS-TR; SS-TR) indicates a non-empty queue. The invention finds particular application in the GPRS/(E)GPRS/GSM environment.

Abstract: The application describes a method and system for controlling a processing of video data such that said video data may be transmitted over a connection in a communication network (I, II), where said connection employs a plurality of protocol layers (L1, L2; AL, NL/TL, LL). The processing of video data for transmission is performed at a first layer (L1; AL). A value or values of one or more transmission condition parameters indicative of transmission conditions in the network (I, II) are acquired, where these transmission condition parameters are specific for a second layer (L2; NL/TL, LL) provided lower than said first layer (L1; AL). Then one or more values of one or more video control parameters usable at said first layer (L1; AL) are derived from said value of said at least one transmission condition parameter and the processing of video data is performed in accordance with the derived one or more values.