ABSTRACT
International Alliance for Interoperability (IAI) is a world wide consortium aiming to define the requirements for software interoperability in the Architecture/Engineering/Construction/Facilities Management industry. The deliverables of IAI are the specifications of Industry Foundation Classes (IFC), an object oriented software library for application development. IFC model is described in EXPRESS, and based in the general architecture of International Organization for Standardization (lSO) 10303-Standard for the Exchange of Product Data (STEP) to describe its reference model. IFC model, described in EXPRESS is based on previously work done by the International Standards Organization Technical Committee 184, Sub Committee 4 ISO TC 184/SC4, namely, ISO10303-1-STEP. Application modules were recently introduced to the STEP architecture and are considered the key components for the new generation of Application Protocols, intending to make them more interoperable, cheaper, quicker to develop, and easier to understand and to manage. The IFC model architecture has been developed using a set of principles governing its organization and structure.
