The Terms used in this Reference Software Specification whose first letter is capital are defined in Table 1. The Terms of MPAI-wide applicability are defined in Table 2.
Table 1 – MPAI-AIF Terms
| Term | Definition |
| Access | Static or slowly changing data that are required by an application such as domain knowledge data, data models, etc. |
| AI Framework (AIF) | The environment where AIWs are executed. |
| AI Module (AIM) | A processing element receiving AIM-specific Inputs and producing AIM-specific Outputs according to its Function. An AIM may be an aggregation of AIMs. AIMs operate in the Trusted Zone. |
| AI Workflow (AIW) | A structured aggregation of AIMs implementing a Use Case receiving AIM-specific inputs and producing AIM-specific outputs according to its Function. AIWs operate in the Trusted Zone. |
| AIF Metadata | The data set describing the capabilities of an AIF set by the AIF Implementer. |
| AIM Metadata | The data set describing the capabilities of an AIM set by the AIM Implementer. |
| AIM Storage | A Component to store data of individual AIMs. An AIM may only access its data. The AIM Storage is part of the Trusted Zone. |
| AIW Metadata | The data set describing the capabilities of an AIW set by the AIW Implementer. |
| Channel | A physical or logical connection between an output Port of an AIM and an input Port of an AIM. The term “connection” is also used as synonymous. Channels are part of the Trusted Zone. |
| Communication | The infrastructure that implements message passing between AIMs. Communication operates in the Trusted Zone. |
| Component | One of the 9 AIF elements: Access, AI Module, AI Workflow, Communication, Controller, AIM Storage, Shared Storage, MPAI Store, and User Agent. |
| Controller | A Component that manages and controls the AIMs in the AIWs, so that they execute in the correct order and at the time when they are needed. The Controller operates in the Trusted Zone. |
| Device | A hardware and/or software entity running at least one instance of an AIF. |
| Event | An occurrence acted on by an Implementation. |
| External Port | An input or output Port simulating communication with an external Controller. |
| Knowledge Base | Structured and/or unstructured information made accessible to AIMs via MPAI-specified interfaces. |
| Message | A sequence of Records. |
| MPAI Ontology | A dynamic collection of terms with defined semantics managed by MPAI. |
| MPAI Server | A remote machine executing one or more AIMs. |
| MPAI Store | The repository of Implementations. |
| Port | A physical or logical communication interface of an AIM. |
| Record | Data with a specified Format. |
| Resource policy | The set of conditions under which specific actions may be applied. |
| Shared Storage | A Component to store data shared among AIMs. The Shared Storage is part of the Trusted Zone. |
| Status | The set of parameters characterising a Component. |
| Structure | A composition of Records |
| Swarm Element | An AIF in in a proximity-based scenario. |
| Time Base | The protocol specifying how Components can access timing information. The \Time Base is part of the Trusted Zone. |
| Topology | The set of Channels connecting AIMs in an AIW. |
| Trusted Zone | An environment that contains only trusted objects, i.e., objects that do not require further authentication. |
| User Agent | The Component interfacing the user with an AIF through the Controller |
| Zero Trust | A cybersecurity model primarily focused on data and service protection that assumes no implicit trust [21]. |
