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What is a NIEM release?

A NIEM release represents a stable, harmonized, and production-ready data model, updated specifications, and potentially enhanced tools. NIEM supports a range of release types that are described in the NIEM High Level Versioning Architecture (HLVA) and categorized by the following release types: Micro, Minor, and Major. NIEM 3.0 will be a major release, building on the current active release NIEM version 2.1. For more information on the HLVA please refer to High-Level Version Architecture pdf.

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When is development of NIEM 3.0 expected to begin?

Work officially began on release 3.0 with the NIEM 3.0 Kick-Off taking place on August 29, 2012. During the kick-off, the NIEM Program Management Office (PMO) shared 3.0 high-level scope, release delivery timeline, and release review and feedback processes. We will update the 3.0 webpage with information as work progresses.

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What will be changing in the NIEM 3.0 Release?

This new release of NIEM is being driven by community requirements to support information exchange. These requirements include model harmonization at both the core and domain level, refactoring of the core to remove and/or add content, incorporation of domain updates as driven by the communities of interest that govern them, and other architectural enhancements such as potential changes in the way NIEM manages code lists. Please reference the dedicated 3.0 webpage for information on the timeline and scope the release.

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What is harmonization?

In NIEM governance, harmonization often refers to the process of examining the model to ensure that a given data element exists only once, and that precise, unambiguous definitions are provided such that those elements are reusable across other domains.

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What does a NIEM 3.0 mean for my existing exchanges?

If you have existing exchanges planned or in operation, no additional action is necessary. NIEM 3.0, once completed, should be the foundation for development of future exchanges, depending on the particular technical requirements of the exchange.

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Will NIEM community members be able to provide input into 3.0 requirements and/or be able to participate in a public review of 3.0?

NIEM community members interested in participating in the 3.0 development process should contact their domain steward to learn if there are any opportunities to participate on NIEM Business Architecture Committee (NBAC) review teams. Members not yet connected to a specific domain can send an email to with “NIEM 3.0 Question" in the subject line and the NIEM PMO will assist you. In addition, all stakeholders are encouraged to participate in the 3.0 beta and release candidate public reviews. A high-level timeline is located on the 3.0 webpage.

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Will the new NIEM-UML Profile be aligned to NIEM 3.0?

Yes, the NIEM-UML Profile will be updated to align to 3.0. The NIEM PMO also plans to support requests by current and prospective NIEM-UML tool vendors to incorporate NIEM 3.0 capabilities into their services.

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How will information be distributed to the NIEM community regarding status of activities, timeline updates, scope definition and milestone achievement? will be your central resource for all NIEM 3.0 information. NIEM community members can also expect to see frequent emails regarding current status and future needs for community involvement as Beta and Release Candidate reviews are scheduled.

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When will NIEM 3.0 be available for implementation?

The release date is tentatively scheduled for fall 2013, potentially as early as October; however this is subject to change. Please visit our 3.0 webpage periodically for updates to the schedule.

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Will there be a difference in the size of NIEM Core from NIEM 2.0 to NIEM 3.0?

NIEM 3.0 Core will be somewhat smaller (than 2.0 Core) as we have moved some elements from Core into more appropriate domains. Furthermore, each inline content element that had a corresponding reference element is now represented by only a single element. On the other hand, a number of AugmentationPoint elements have been added to NIEM Core (as well as domains) to support the new augmentation technique. The net reduction in Core size will be about 50-60 fewer types and elements.

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Will it be easier to construct the NIEM conformant schemas in Version 3.0?

Changes to the NIEM technical architecture in 3.0 will make it a little easier to create a NIEM-conformant schema. Augmentations are less complex and somewhat more visible. Code lists can all be easily extended by users/developers as needed using element substitution. All elements will be able to bear content (inline) or reference another identical element that carries content (for example, an nc:Person element in an XML instance can contain person properties with content values or reference another nc:Person element that contains the properties. structures.xsd may now be subset in an IEPD by users. appinfo.xsd will provide several improvements for clarity of conformance targets and local terminology within annotations. We believe these changes have made NIEM-conformant schemas simpler, more flexible, and easier to understand and build with NIEM 3.0.

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In Version 3.0 will there be a preference for using attributes over elements? If yes, why?

No. The rationale for elements vs. attributes in NIEM remains the same: The NIEM release will use elements to model NIEM properties, unless this is not possible (usually due to a type having simple content), in which case it will use attributes. This is so that properties may be extended, restricted, and specialized (using substitution groups) by IEPDs, none of which is possible with attributes.

That said, we have only changed appinfo.xsd to employ attributes (instead of element properties) for several reasons. The appinfo schema defines metadata about the model, schemas, and terminology, and does not contain payload content components. Appinfo is part of NIEM infrastructure that is designed to be relatively fixed, and does not require the flexibility that users/developers need for IEPD extension and corresponding model semantics. And finally, attributes tend to make appinfo annotations simpler and cleaner.

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Are there any significant updates to the SSGT and the Wantlist generation?

Schema Subset Generation Tool (SSGT) is being updated to the 3.0 architecture. The Wantlist is essentially a format for saving the subset. There are no significant changes to the Wantlist format. There are some Wantlist values that will not be used in 3.0 (for example, there is no longer a need to distinguish an element that is a reference to content vs. an element that bears the content inline). Thus, the Wantlist v2.0 schema will be valid for either a NIEM 2.0, 2.1, or 3.0 subset; however, in a 3.0 subset some attribute values will be ignored.

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How will IC-ISM be embedded within NIEM 3.0? What is the architectural approach? Will the beta have documentation on IC-ISM changes?

The IC-ISM XML Schemas will not be included as part of the NIEM 3.0 release. Instead, each of the NIEM structures base types (ObjectType, AssociationType, AugmentationType, and MetadataType, as well as SimpleObjectAttributeGroup) incorporates an anyAttributes element as part of its definition. This wildcard allows any attributes to appear that have the IC-ISM namespace, as well as those having the IC-NTK namespace. This is in line with the recommendations of the developer of the IC Trusted Data Framework, and should support ISM, NTK, and the TDF. Developers that need schemas for these namespaces should download them from an authoritative source.

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