DGN

This article is about the computer file format. For the Illinois high school, see Downers Grove North.

DGN (Design) is the name used for CAD file formats supported by Bentley Systems' MicroStation and Intergraph's Interactive Graphics Design System (IGDS) CAD programs.

There are two versions of DGN:

• Up until 2000, all DGN files were based on the Intergraph Standard File Formats (ISFF) specification, published in the late 1980s by Intergraph. Sometimes referred to as V7 DGN, or Intergraph DGN.

• In 2000, Bentley Systems created an updated version of DGN which includes a superset of DGN's capabilities, but which has a different internal data structure than the ISFF-based DGN. This version is properly referred to as V8 DGN.

The DGN format is used in many large projects, including buildings, highways, bridges, process plants, shipbuilding.Although DGN is not as widely-used as Autodesk's DWG.

In 2008 Autodesk and Bentley agreed on exchange of software libraries, including Autodesk RealDWG, to improve the ability to read and write the companies' respective DWG and DGN formats in mixed environments with greater fidelity. In addition, the two companies will facilitate work process interoperability between their AEC applications through supporting the reciprocal use of available Application Programming Interfaces (APIs).

External links

• OpenDGN - Bentley's OpenDGN initiative
• Microstation 95/ISFF Description (pdf) - Information on the ISFF/DGN file format as distributed with Microstation 95.
• ISFF Specification - Intergraph Standard File Formats (Element Structure)
• DGNLib - DGNLib: a free Microstation DGN (ISFF) program library
• DGNdirect - DGNdirect, from Open Design Alliance: a V8/V7 DGN program library.