Definition
Functional Requirements
Syntax
Semantics
Conformance
Performance
1 Definition
An Ego‑Remote AMS Message is a Message exchanged between the AMS of an Ego CAV and the AMS of a Remote CAV. It enables the Ego CAV to obtain the Remote CAV’s interpretation of a portion of its Environment corresponding to the Ego CAV’s intended U‑Location. The Message may contain:
- A Request/Response relating to the M‑Location corresponding to the intended U‑Location.
- The Trajectory the Ego CAV intends to adopt.
2 Functional Requirements
The interaction between Ego and Remote CAVs unfolds as follows:
- Request Phase – The Ego CAV sends an Ego‑Remote AMS Message requesting how the Remote CAV interprets a specific subset of its Environment corresponding to the intended U‑Location.
- Remote CAV Processing – Upon accepting the request, the Remote CAV:
- Converts the requested U‑Location into the corresponding M‑Location in its Full Environment Descriptors (FED).
- Extracts the FED subset corresponding to that M‑Location using its scene‑based object structure.
- Adapts the level of detail to the bandwidth currently available.
- Sends the M‑Location and the relevant FED subset to the Ego CAV.
- Ego CAV Processing – Upon receiving the Response, the Ego CAV:
- Reconciles its own M‑Location understanding with the Remote CAV’s data.
- Records major discrepancies between its own Positions and those inferred from the Remote FED.
CAV-TEC V2.0 exchanges the Ego-Remote AMS Message over the External transport of MPAI-AIF V3.0, between the Controllers of CAVs in range, each message signed by the sending CAV and verified by the receiving one; the CAVs of a city are admitted by its Trust Authority. It does not address privacy requirements related to hiding the identity of the CAV providing information from its Full Environment Descriptors.
3 Syntax
https://schemas.mpai.community/CAV2/V2.0/data/EgoRemoteAMSMessage.json
4 Semantics
Table 1 specifies the semantics of the Ego-Remote AMS Message Data Type.
| Label | Type | Req. | Description |
|---|---|---|---|
| Header | string (CAV-ERA-V2.0) | Yes | Ego-Remote AMS Message Header – Standard CAV-ERA-Vx.y |
| MInstanceID | string | Identifier of the M-Instance (Virtual Space) associated with this Ego-Remote AMS Message. | |
| UEnvironmentID | string | Identifier of the U-Environment (Real Space) associated with this Ego-Remote AMS Message. | |
| EgoRemoteAMSMessageID | string | Yes | Unique identifier of this Ego-Remote AMS Message instance. |
| EgoRemoteAMSMessageTime | Simple Time | Time this Ego-Remote AMS Message was produced. | |
| EgoRemoteAMSMessageSpaceTime | Simple Time | Space/Time where/when this Ego-Remote AMS Message applies. | |
| CAVIdentifier | string | Identifier of the CAV sending this message. | |
| Message | Yes | One of the five message types exchanged between Ego and Remote AMS. | |
| DataXMData | Data Exchange Metadata | MPAI-PTF Data Exchange Metadata providing provenance, authorisation, legal, security, and confidence information associated with this Ego-Remote AMS Message in a trusted data exchange context. | |
| DescrMetadata | string | Human-readable descriptive metadata of the Ego-Remote AMS Message (plain text, max 2048 characters). |
5 Conformance Testing
Data conform to the Ego-Remote AMS Message Data Type when they validate against its schema. If the schema references other schemas, data referencing a secondary schema shall also validate against that schema, if present, and conform with the Qualifier, if present.
