configuration item

A configuration item (CI) is any uniquely identifiable component that is placed under formal configuration management so that its version, attributes, relationships, and changes can be controlled and traced over time.

What a configuration item typically includes

In industrial and regulated manufacturing environments, a configuration item commonly refers to one of the following types of managed objects:

• Physical hardware such as an aircraft line-replaceable unit (LRU), machine controller, sensor, or production tool.
• Software and firmware such as embedded control software, MES or ERP application versions, PLC programs, or MRO‑released software loads.
• Documentation and data such as controlled work instructions, maintenance procedures, wiring diagrams, BOMs, routings, or CNC programs.
• Configured assemblies and products such as a specific aircraft tail number, engine serial number, or configured equipment model with defined options.

Each CI is typically assigned a unique identifier (part number, configuration ID, or similar) and is subject to defined processes for identification, change control, approval, release, and record retention.

How configuration items are used operationally

Within OT/IT, MES, PLM, ERP, and quality systems, configuration items are used to:

• Record baselines that capture an approved set of hardware, software, and documents at a point in time (for example, a certified aircraft configuration).
• Control changes so that any modification to a CI, or its relationships to other CIs, is evaluated, approved, implemented, and documented.
• Maintain traceability between CIs, such as linking software versions to hardware part numbers, serial numbers, aircraft tail numbers, or work orders.
• Support investigations and audits by showing exactly which CI versions were installed, used, or in effect at a given time, location, or unit.

In aerospace, for example, an aircraft control computer, its installed software load, associated configuration files, and the governing maintenance manual revision may each be managed as separate configuration items, linked together in PLM, QMS, ERP, and MRO systems.

What a configuration item is not

A configuration item is not simply any file or object that exists in a system. It is:

• Formally selected for configuration control due to its impact on safety, performance, compliance, or maintainability.
• Managed through defined procedures for identification, versioning, and change approval.
• Traceable over its lifecycle from creation and release to modification, retirement, or replacement.

Temporary test files, ad hoc spreadsheets, or informal notes typically are not treated as configuration items unless an organization explicitly brings them under configuration control.

Common confusion

• Configuration item vs. configuration baseline: A configuration item is a single managed component. A baseline is an agreed collection of CI versions that define a product or system state at a specific point in time.
• Configuration item vs. asset: An asset is anything of value to the organization (for example a machine). A configuration item is anything that is formally configuration-controlled. Many assets are also CIs, but some CIs are not physical assets (for example a software version or specification document).
• Configuration item vs. requirement: Requirements may be documented inside a CI (such as a specification), but the requirement itself is not usually treated as a CI unless the organization explicitly manages it that way.

Link to aerospace software configuration management

In aerospace and AS9100 contexts, software executables, parameter sets, configuration files, and even specific software loads tied to an aircraft tail number can each be managed as configuration items. Organizations are expected to:

• Uniquely identify these CIs and their versions.
• Control and document changes through defined authorities and workflows.
• Maintain traceable links across QMS, PLM, ERP, and MRO systems so the installed configuration of each aircraft or serialized product can be reconstructed when required.