Handling of packets in order to communicate with a machine over one or more secondary networks

The method involves obtaining identification data of a gateway (GW1) intervening in transmission of a data packet, where the data is extracted from the data packet. Decoding function (FD1) associated to the obtained data is identified, where the function is an inverse function of a coding function (FC1) applied by the gateway to the packet before transmission of the packet. The data packet received by a receiver entity is decoded by applying the identified function. Independent claims are also included for the following: (1) a method of processing a data packet to be transmitted by an emitter entity (2) a communication device for receiving a data packet (3) a communication device for transmitting a data packet (4) a computer program comprising program code instructions for implementing a data packet processing method (5) a processor readable recording medium for recording a computer program comprising program code instructions for implementing a data packet processing method.