Infrastructure Data Taxonomy

Infrastructure and its elements can be described and categorized in various ways. Industries operating in various sectors of the nation’s infrastructure, for example, often use the same term to refer to very different things. Terminology is likewise varied among government agencies at the Federal, State, and local levels. The Infrastructure Data Taxonomy (IDT) establishes a detailed and structured terminology that facilitates data discovery, management, and enables data sharing among mission partners and systems.

The Department of Homeland Security Office of Infrastructure Protection (IP) created the IDT to serve as a nomenclature that can be used by the infrastructure protection community and industry partners to categorize infrastructure assets and establish a common language for all to utilize.

Common Terminology for Describing Critical Infrastructure

The Taxonomy supports a more efficient data integration and transfer of data between systems, which provides a foundation for numerous applications that focus on the identification, collection, and sharing of the nation’s critical infrastructure information. By applying a detailed, structured system to help categorize assets by sectors, sub-sectors, segments, sub-segments, and asset types, the IDT minimizes the potential for confusion.

How to Access the Infrastructure Data Taxonomy

Mission partners can request access to the taxonomy by completing the registration form on the Taxonomy Portal.

If you already have an IDT account, login to access the portal to download, view, or comment on the IDT.

How Is the Infrastructure Data Taxonomy Used?

The IDT Table of Contents serves as a quick reference of the taxonomy, in which infrastructure assets are categorized up to five levels. The first level is determined by broad infrastructure categories, which are then detailed further by increasingly granular differentiators as needed. The five levels of differentiation found within the IDT are the sector, sub-sector, segment, sub-segment, and asset type.

In describing a given infrastructure asset, the general convention is to use the greatest level of detail possible. If there is insufficient information to identify an asset at a greater level of detail, a less-detailed level may be used.

Some infrastructure assets fall into multiple categories of the taxonomy. For this reason, some concepts may be found listed within multiple sectors. This is called a cross-sector reference.

For example, in referring to the same nuclear power plant, the government and private sector could reference it either as a nuclear plant, a nuclear site, or a nuclear facility. The example below shows how this specific nuclear facility would be classified using the IDT:

  • Sector: The nuclear plant is identified as being part of the Nuclear Reactors, Materials, and Waste Sector.
    • Subsector: Within the Nuclear Reactors, Materials, and Waste Sector, the nuclear plant is designated as part of the Nuclear Facility Subsector.
      • Segment: The nuclear plant is identified as part of the Nuclear Power Plant Segment to recognize the plant’s purpose.
        • Subsegment: Finally, the nuclear plant can be categorized as being part of the Boiling Water Reactor Subsegment to recognize how the plant produces energy.


Learn how the Infrastructure Data Taxonomy can support your organization's homeland security efforts by contacting the IP Gateway Help Desk at or 1-866-844-8163.

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