A mobile data network includes a radio access network and a core network. A first service mechanism in the radio access network breaks out data coming from a basestation. When data is broken out by the first service mechanism, the data is delivered at the edge, which means the true activity of the channel is not visible to the core network. The reduction of data in the core network due to serving data at the edge risks causing a switch from a high-speed channel to a low-speed channel by the mechanism in the core network that monitors and assigns channel speeds. In order to maintain the high-speed channel, the on-going data rate for a subscriber session is monitored and channel maintenance traffic is injected towards and from the radio network controller (in both directions). The amount of channel maintenance traffic depends on thresholds that determine a desired data rate.