A device (D1) is intended for processing digital data frames to be transmitted by a transport network (TN), and comprises i) a first processing means (PM1) comprising ports for receiving digital data frames and arranged for downsizing, then compressing, if necessary, and then compacting each one of these received digital data frames to produce reduced digital data frames, ii) a second processing means (PM2) arranged for aggregating at least some of these reduced digital data frames together according to aggregation information to produce frame groups, and iii) a third processing means (PM3) arranged for grouping these frame groups together with a group descriptor, defining initial arrangements of the digital data frames, according to grouping information, to produce a transport frame to be transmitted by the transport network (TN).