A network node comprising an input, a processor and an output, the processor being coupled to the input and the output; the input and output both being connected to at least one network; in which the processor is arranged so as to receive from the input an executable application and an associated set of requirements for the application, in which the processor is arranged to determine, on receipt of an application and the associated set of requirements, a set of destination network nodes which are reachable through at least one network, to which the output is connected based upon the requirements and to send the application to the destination nodes through the output. Thus, an application can be distributed through a telecommunications network specifying only the requirements that a destination network must satisfy, rather than the addresses of the destination network nodes. Furthermore, the application can be transferred between network nodes should user equipment move through the network.