What is IMDF? It means Indoor Mapping Information Layout. And also what, then is interior mapping? It allows sensors or mobile phones to be tracked in an internal atmosphere. And also esri.com calls it innovative. They describe it as a means to show data on a 2D or 3D http://emiliorhaq493826.isblog.net/indoor-mapping-data-as-well-as-the-future-17851668