Data communications, including issuing, by an application program to a high level data communications library, a request for initialization of a data communications service; issuing to a low level data communications library a request for registration of data communications functions; registering the data communications functions, including instantiating a factory object for each of the one or more data communications functions; issuing by the application program an instruction to execute a designated data communications function; issuing, to the low level data communications library, an instruction to execute the designated data communications function, including passing to the low level data communications library a call parameter that identifies a factory object; creating with the identified factory object the data communications object that implements the data communications function according to the protocol; and executing by the low level data communications library the designated data communications function.