The invention relates to a method for data exchange between network elements with a first network element (A), arranged in a first network domain (DMA) with an address (ADA) valid in the first network domain (DMA), a second network element (B), arranged in a second network domain (DMB) with an address (ADB) valid in the first network domain (DMA) and a network gateway (GW), arranged between the network domains (DMA,DMB), for the forwarding of a data packet (DP) for sending, from the first network element (A) to the second network element (B), said data packet (DP) comprising a characterising range (HEAD) and a data range (DATA). In the characterising range (HEAD) of the data packet (DP), a conversion of the target address (ADB), characterising the receiving network element (B), into a target address (ADB') valid in the second network domain (DMB) is carried out under control of the network gateway (GW). The first network element (A) thus enters the source address thereof to be entered in the data range (DATA) of the data packet (DP) as the source address of the first network element (ADA') valid in the second network (DMB)in the data range (DATA).