RAMI 4.0, the Reference Architecture Model Industrie 4.0, is a three-dimensional map that gives every Industrie 4.0 asset, standard and use case one shared place to be described. It was published in 2015 by the German industry association ZVEI and the VDI/VDE Society for Measurement and Automatic Control (GMA), under Plattform Industrie 4.0, and was standardised the following year as DIN SPEC 91345. The model organises Industrie 4.0 along three axes: Layers, Life Cycle and Value Stream, and Hierarchy Levels. This guide explains each axis accurately, along with the Asset Administration Shell that brings the model to life and where the standard stands today.
| Attribute | Detail |
|---|---|
| Full name | Reference Architecture Model Industrie 4.0 |
| Abbreviation | RAMI 4.0 (also written RAMI4.0) |
| Introduced | 2015 (presented at Hannover Messe 2015) |
| Developed by | ZVEI and VDI/VDE-GMA, under Plattform Industrie 4.0 (founded by BITKOM, VDMA and ZVEI) |
| Standardised as | DIN SPEC 91345 (April 2016); formerly IEC PAS 63088 (2017, withdrawn 2024) |
| Structure | A three-dimensional model with three axes: Layers, Life Cycle and Value Stream, and Hierarchy Levels |
| Built on | SGAM (smart grid model), IEC 62264 / IEC 61512 (hierarchy) and IEC 62890 (life cycle) |
| Companion concept | The Asset Administration Shell (now IEC 63278-1:2023) |
| Purpose | Give every Industrie 4.0 asset and standard one shared place to be classified so they can interoperate |
What is RAMI 4.0?
RAMI 4.0 is a reference model, not a piece of software. It takes the many parts of Industry 4.0, which come from fields as different as process engineering and factory automation, and arranges them in a single three-dimensional frame so they can be compared and made to work together. Any asset, from a bolt to a whole plant, can be located somewhere in the cube, which is what makes heterogeneous standards interoperable.
A common misconception is that RAMI 4.0 has five layers called people, data, things, processes and outcomes. That is incorrect. RAMI 4.0 has six layers on its vertical axis, and they describe an asset from its business role down to the physical thing itself: Business, Functional, Information, Communication, Integration and Asset. The full detail is in the Layers section below.
One more idea sits at the heart of RAMI 4.0: it deliberately breaks up the rigid automation pyramid. Instead of fixed equipment tiers, the model uses a flexible, service-oriented view in which functions and responsibilities, rather than boxes of hardware, are what matter. That is the shift RAMI 4.0 is built to describe.
Why RAMI 4.0 exists
Industrie 4.0 brings together groups with very different histories and standards: the process industries, discrete manufacturing, factory automation and IT. Left alone, each keeps its own information and communication technologies, and nothing connects. RAMI 4.0 gives them a common reference frame so that existing standards can be located and compared, gaps and overlaps can be found, a preferred standard can be chosen for each issue, and companies can migrate from their current systems toward Industrie 4.0 step by step. Its aim, in the words of the original report, is to cover the issues with as few standards as possible.
The three axes of RAMI 4.0
RAMI 4.0 is a cube built from three axes. The vertical axis holds the six layers; the left horizontal axis is the life cycle and value stream; the right horizontal axis is the hierarchy of levels in and around the factory. Any Industrie 4.0 element can be given a position on all three at once.
Axis 1: Layers
The vertical axis breaks an asset into six layers, from its business role at the top to the physical thing at the bottom. Each layer has a clear responsibility, layers are loosely coupled, and information passes only between neighbouring layers. This structure is adapted from the Smart Grid Architecture Model (SGAM), with an Asset layer at the base and a new Integration layer added above it.
| Layer (top to bottom) | What it represents |
|---|---|
| Business | The business model and the overall process: business objectives, legal and regulatory conditions, and the orchestration of the services below it. It does not hold concrete systems such as ERP. |
| Functional | The runtime and modelling environment for the services and rules that support business processes. This is where decision logic sits and where functions are integrated horizontally. |
| Information | Holds and pre-processes the data and models, keeps that data consistent and correct, and exposes it through service interfaces. |
| Communication | Standardises access to the Information layer using a uniform data format. The report names OPC UA (IEC 62541) as its basis. |
| Integration | The transition from the real world to the digital one: it makes asset information computer-processable, generates events from assets, and holds sensors, RFID readers and the human-machine interface, where people interact with the system. |
| Asset | Reality itself: physical things such as machines and parts, plus documents, drawings and even people. It connects passively to the Integration layer, for example through a QR code. |
Axis 2: Life Cycle and Value Stream
The left horizontal axis, based on IEC 62890, follows an asset through its life. It distinguishes a Type from an Instance. A Type is the idea as it is designed, developed and tested up to the first prototype; once validated, the Type is released for series production. Every item then built from that design is an Instance, for example a specific product with its own serial number. The relationship can recur along the value chain: to a customer, a delivered product may again be a Type until it is installed in a particular system, at which point it becomes an Instance. Each half of the axis runs from development or production into ongoing maintenance and usage.
Axis 3: Hierarchy Levels
The right horizontal axis places the asset in the factory hierarchy. It is based on IEC 62264 (ISA-95) and IEC 61512 (ISA-88), but describes functions and responsibilities rather than the fixed tiers of the classical automation pyramid. RAMI 4.0 extends the classic range with three additions: Connected World at the top, for collaboration beyond a single factory, and Field Device and Product at the bottom, so that a smart sensor and the workpiece itself both have a place in the model.
| Hierarchy level (top to bottom) | Origin |
|---|---|
| Connected World | Added for Industrie 4.0: collaboration that reaches beyond a single factory or company. |
| Enterprise | From IEC 62264 (ISA-95). |
| Work Centers | From IEC 62264 (ISA-95). |
| Station | From IEC 62264 and IEC 61512. |
| Control Device | From IEC 62264 and IEC 61512. |
| Field Device | Added for Industrie 4.0: an intelligent field device, such as a smart sensor. |
| Product | Added for Industrie 4.0: the workpiece or product itself is now part of the model. |
The Asset Administration Shell
RAMI 4.0 describes where things belong; the Asset Administration Shell (in German, Verwaltungsschale) is what actually puts an asset into that model. An asset on its own is not yet part of Industrie 4.0. Only once it is wrapped in an administration shell does it become an I4.0 component. As the original report puts it, an administration shell turns an object into an I4.0 component.
The shell holds two things: the asset’s virtual representation (its data and models) and its technical functionality, together with a manifest that lists what the shell contains. In RAMI 4.0 terms, that virtual representation lives in the Information layer and the functionality in the Functional layer, so the shell is the bridge that lets a real asset be addressed and reused across the whole cube. The Asset Administration Shell is the operational core of the Industrie 4.0 digital twin, and it is where standardisation is most active today: it is now defined by IEC 63278-1:2023 and maintained through the Industrial Digital Twin Association (IDTA), which publishes the current AAS specification.
RAMI 4.0 vs IIRA
RAMI 4.0 is often compared with the Industrial Internet Reference Architecture (IIRA), which came out of the United States at around the same time. They start from different places but were later found to fit together rather than compete.
| RAMI 4.0 | IIRA | |
|---|---|---|
| Full name | Reference Architecture Model Industrie 4.0 | Industrial Internet Reference Architecture |
| Origin | Germany: Plattform Industrie 4.0 / ZVEI / VDI-VDE-GMA (2015) | United States: Industrial Internet Consortium (2014) |
| Focus | Manufacturing and its value-chain life cycles; a concrete 3D reference model | Cross-industry Industrial IoT; a broad architecture framework |
| Formalised in | DIN SPEC 91345 (2016) | A framework published by the Industrial Internet Consortium |
| Relationship | Mapped as complementary in a joint IIC and Plattform Industrie 4.0 white paper (2018) | The same joint mapping applies |
Where RAMI 4.0 stands today
RAMI 4.0 is still the reference architecture model for Industrie 4.0 and has not been replaced by a rival model. It remains published as DIN SPEC 91345 (April 2016). Its international form, IEC PAS 63088 (2017), was withdrawn in September 2024; that is the normal end of life for a Publicly Available Specification rather than a sign the model is obsolete. The live standardisation work has moved to the Asset Administration Shell (IEC 63278 and the IDTA specifications), which is the practical way RAMI 4.0 is being realised in industry.
Sources
- ZVEI and VDI/VDE-GMA, Status Report: Reference Architecture Model Industrie 4.0 (RAMI4.0), 2015 (the defining document).
- DIN SPEC 91345:2016-04, Reference Architecture Model Industrie 4.0 (RAMI4.0).
- IEC 63278-1:2023, Asset Administration Shell for industrial applications, Part 1.
What is RAMI 4.0?
RAMI 4.0, the Reference Architecture Model Industrie 4.0, is a three-dimensional map that lets every Industrie 4.0 asset, standard and use case be placed in one common frame. It was published in 2015 by ZVEI and VDI/VDE-GMA under Plattform Industrie 4.0 and standardised as DIN SPEC 91345 in 2016. Its three axes are Layers, Life Cycle and Value Stream, and Hierarchy Levels.
What are the three axes of RAMI 4.0?
The vertical axis is Layers (six interoperability layers, from Business down to Asset). The left horizontal axis is Life Cycle and Value Stream, based on IEC 62890, which splits an asset into Type and Instance. The right horizontal axis is Hierarchy Levels, based on IEC 62264 and IEC 61512 and extended for Industrie 4.0.
What are the six layers of RAMI 4.0?
From top to bottom they are Business, Functional, Information, Communication, Integration and Asset. Note that RAMI 4.0 has six layers, not the five that some sources list; the six layers describe an asset from its business role down to the physical thing itself.
What is the Asset Administration Shell in RAMI 4.0?
The Asset Administration Shell (Verwaltungsschale) is the standardised digital representation of an asset. An asset combined with its administration shell is called an I4.0 component. The shell holds the asset data and technical functionality, which is how the asset is placed inside the RAMI 4.0 model. It is now standardised as IEC 63278-1:2023 and maintained by the Industrial Digital Twin Association.
Who developed RAMI 4.0 and when?
RAMI 4.0 was developed in 2015 by the German electrical-industry association ZVEI together with the VDI/VDE Society for Measurement and Automatic Control (GMA), under the umbrella of Plattform Industrie 4.0. It was formalised as DIN SPEC 91345 in 2016 and, for a time, as IEC PAS 63088 (2017, withdrawn in 2024).