Abstract: According to an aspect, there is provided a first apparatus for performing the following. The first apparatus transmits a first protocol data unit, PDU, using enhanced common public radio interface, eCPRI, to a second apparatus. The first PDU comprises a first header and, as payload, at least a first label for the first header. Said first label comprises at least a compressed eCPRI header. Following the transmitting of the first PDU, the first apparatus transmits a second PDU without a header using eCPRI to the second apparatus. The second PDU corresponds to the first header and comprises a second label comprising at least said eCPRI header for enabling accessing of the first header locally by the second apparatus.