Abstract: A computer implemented interface for interfacing an equipment controller to an equipment manager each arranged to respond to a reproduced text messages according to a first and second protocol, respectively. The interface comprises a number of program modules (502-514) which each receive one or more inputs and produce an output dependent on whether defined conditions are met by the inputs. A number of the outputs of the program modules constitute inputs to other program modules therefore defining a network. A number of the program modules (502-508) are of the type which is responsive to a predefined text in a respective field of an input message to produce an output to a further program module which is responsive to a further predefined text in another field which is valid in a first protocol in the context of the predefined text. The network of program modules produces a series of outputs which represent the information content of the original input message.