Abstract: A telecommunication network node is proposed which provides a novel solution to the realignment of payload of an input datastream (IN) within an output datastream (OUT) after dismantling the former. The present network node thereto generates from the payload of the input datastream (IN) data units (MSCI) some of which include a time label (TL) indicative of the moment at which they are derived. These data units (MSCI) are stored in a buffer (BM) from which they are read at a varying rate determined to track the input data rate and constituting the output data rate. This tracking is achieved by using the time labels to calculate a node delay, i.e. the delay between the derivation and the reading of a data unit, and by changing the above rate as a function of this node delay in order to keep it within predetermined bounds.