The handing over of data between two Façades is done by Data Transfer Files in RDF/XML format.

Data Transfer Files are also used to transfer data mapped from the internal format of any User System to the Data Transfer File format to the System Façade of that User System.

Three examples are given here.

Please note that there are in fact two different types of Transfer File:

• the Transfer File from the mapping results of a User System to a Façade - that type contains the "transmission information", simply because that has to be stored in that facade;
• the Transfer File from one Façade to another Façade - the "transmission information" remains stored in the sending Façade, and in the Transfer File only a reference to that information is made, so that the recipient can trace it.