A technique for operating an RNC of a communication network during a soft handover process of a mobile terminal between a first BS and at least one second BS that are connected to the RNC is provided. A method implementation of the technique comprises receiving, at a MAC protocol layer of the RNC, a first data frame stream from the first BS via a first data path and a second data frame stream from the second BS via a second data path. A relative delay between the data frames of the first and the second data frame stream regarding their arrival at the RNC is determined. The relative delay takes into account different systematic propagation durations from the first BS and the second BS to the RNC. At then the MAC protocol layer, data frames of the first and the second data frame stream are then merged into a third data frame stream which is transmitted to a protocol layer above the MAC protocol layer. The merging of the data frames is carried out in dependence on the relative delay.