1. A method of mapping communication between an application of a communications device and any one of a plurality of application servers of a communications network, the application of the communications device using a first communication protocol and each application server using a respective second communication protocol, the method being executed by a broker server of the communications network and comprising: maintaining a protocol mapping between the first communication protocol and each second communication protocol, the protocol mapping being based on a non-compiled editable file describing the protocol mapping; determining which application server is involved in the communication and which second communication protocol is used by that application server for the communication; and mapping communication between the application of the communications device and the application server involved in the communication using the protocol mapping between the first communication protocol and the second communication protocol used by that application server; and updating the protocol mapping by updating the non-compiled editable file to reflect any changes to the first communication protocol or the second communication protocol that have occurred without updating any compiled software; wherein determining which application server is involved in the communication comprises using an application identifier built into the first protocol to identify the application server among the plurality of application servers of the communications network.