Radio access node registration for multimedia broadcast multicast service

摘要

A radio network control node acts across an Iur interface as a drift radio network control node ( 262 ) for a user equipment unit (UE) in a communications system supporting a multimedia broadcast multicast service (MBMS). The drift radio network control node ( 262 ) maintains a first counter for counting a number of events occurring at the drift radio network control node ( 262 ). Registration of the drift radio network control node ( 262 ) with a core network node ( 30 ) is advantageously delayed until the counter has exceeded a first threshold value. In one example mode, the number of events occurring at the drift network control node ( 262 ) which is counted by the counter is a number of user equipment units for which a Iur linking procedure is performed for the MBMS session. In another example mode, the number of events occurring at the drift network control node ( 262 ) which is counted by the counter are time periods elapsed since an Iur linking procedure for the MEMS session has been performed for a predetermined user equipment unit.