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Updated Model Package Description Specification Now Available

Model Package Description (MPD) Specification version 3.0 was published in August 2014 as a result of NIEM release version 3.0. For the most part, the new MPD Specification 3.0.1 (10 April 2015) is the same as 3.0. In 3.0.1, we simply applied a few minor refinements to enhance clarity and understanding. Changes are as follows:

  • Revises and clarifies the MPD ZIP file format requirement. Allows an MPD to live as a file collection in a repository, such as a Git repository. An MPD can still use ZIP file format for transit, upload, download, bulk storage, or whenever convenient to maintain a smaller electronic footprint.
  • All former references to "core update" are now "core supplement".
  • Changes a "core supplement" (formerly core update) from a type of MPD to a special type of "release" MPD.  The specification now defines only four MPD classes: release (that subsume core supplement), domain update, Information Exchange Package Documentation (IEPD), and Enterprise Information Exchange Model (EIEM).
  • Adds to Section 1.3 "Scope": MPD 3.0.1 is applicable to all MPDs in general, but is specifically focused on IEPDs.
  • Adds to Section 1.3.1 "Information Exchange Package Documentation": MPD 3.0.1 does not address IEPD versioning (except a version numbering scheme). IEPDs are managed and versioned independently of the Core and domains. The NIEM Technical Architecture Committee is currently working to provide some guidance on IEPD versioning for the community to leverage. Once the guidance is finalized, it will be posted to the NIEM GitHub site.

Access the MPD Specification 3.0.1 at