A method for traffic control in a cellular telephony system (100), each cell comprising at least one node, an RBS (130), for the control of traffic to and from users (150) in the cell. The traffic to each UE (150) can comprise at least one flow, and the method is intended for control of the flows in the traffic to UEs (150) in the system (100). and comprises one control function for each controlled flow to each of said UEs (150). Said control function comprises a congestion avoidance function (240, 440) which detects the presence or absence of congestion in a flow to an UE (150), and which, upon congestion or low utilization of the network reduces the bit rate to the UE (150) in a non-linear fashion, and which, in the absence of congestion, linearly increases the bit rate of the traffic to the UE (150).