A cellular communication system comprises a network based radio bearer controller (123) which is arranged to control and manage the setup and operation of radio bearers. The radio bearer controller comprises a RAB processor (201) which is arranged to set up a plurality of user plane radio bearers for a user equipment (101). The plurality of user plane radio bearers all support a common service. The radio bearer controller (123) further comprises a link processor (203) which links the plurality of user plane radio bearers. The radio bearer controller (123) can process linked user plane radio bearers in relation to each other, for example by terminating all linked user plane radio bearers if a single radio bearer fails. The invention may be particularly suitable for a UMTS (Universal Mobile Telecommunication System) communication system supporting services using a plurality of UMTS user plane radio bearers.