Data is distributed over multiple connections through a network in successive groups of containers such that respective containers of each group are transmitted via respective ones of the connections. Each container contains an identifier of the group to which the container belongs. The output of the network data from containers that have been received is buffered to compensate differences in the delays of transport via different connections. An oldest identifier value received via the connections during a time frame is detected by determining a plurality of respective minimum values of the identifiers received in the time frame. Each minimum value is determined among received identifiers from a respective sub-range of possible identifier values. A "sequentially first" sub-range of successive sub-ranges, for which at least one of the minimum values has been determined, is then determined. The minimum value of the "sequentially first" sub-range is then selected as the oldest identifier.