1. Introduction
Unlike outdoor environment which has been the focus of uGIS development for years, Indoor GIS is still in its infancy to cope with the new Ubiquitous Computing (Ubicomp) technology. The advent of ubiquitous technology has led to the stage which requires the new consideration on how to define and create building data for Indoor GIS services. As many new technologies are embedded into buildings, the indoor environment has become smart and interactive with the context. This new and dynamic property, so far, cannot be supported by existing CAD and GIS standard. Existing BIM and GIS Standards such as Industry Foundation Classes (IFCs), OpenGIS and CityGML cannot explain the information of indoor environment in detail. In addition, as indoor environment has been becoming more complicated so far there is no solution to integrate U-service related components into spatial data model of indoor environment. To solve this problem, it is, thus, indispensable to construct a novel framework in which the outcome building information model can be extensively shared among Indoor GIS applications and services.