Why can I easily interchange BPMN models between BPMN modeling tools?
While the XMI (XML Metadata Interchange) standard purports to facilitate the interchange of OMG models, it has been largely ineffective in practice. There are at least two technical reasons for this. First and foremost, XMI attempts to solve a technical problem far more difficult than exchanging models for specific modeling languages, such as BPMN; it attempts to provide a mechanism for facilitating the exchange of any arbitrary language defined by the OMG’s Metamodel Object Facility (MOF). Secondly, the OMG has failed to define complete diagram interchange specifications for its visual modeling languages. Since BPMN is a visual modeling language, this shortcoming is a showstopper for many modelers who don’t want to redraw their diagrams. Any modeler can empirically verify this shortcoming by defining a BPMN 1.x model in one modeling tool, and attempting to import it into another modeling tool without any loss of information.
