3.3.11.6. ECU Variant Detection

Software Architecture: ECU Variant Detection via SOVD-API arch~sovd-api-ecu-variant-detection
status: draft
links outgoing: dimpl~sovd-api-ecu-variant-detection
links incoming: req~sovd-api-ecu-variant-detection

Motivation

Some ECUs have different variants, which support different functionality. To provide the correct functionality, the CDA needs to be able to detect the variant in use. This variant may change at any point due to the nature of the ECUs software. Clients may need to trigger this explicitly to ensure correct functionality.

Variant Detection Trigger

A PUT on the path /components/{ecuName} must trigger a variant detection

' SPDX-FileCopyrightText: 2026 Copyright (c) Contributors to the Eclipse Foundation ' ' See the NOTICE file(s) distributed with this work for additional ' information regarding copyright ownership. ' ' This program and the accompanying materials are made available under the ' terms of the Apache License Version 2.0 which is available at ' https://www.apache.org/licenses/LICENSE-2.0 ' ' SPDX-License-Identifier: Apache-2.0 @startuml title ECU Variant Detection participant Client participant "HTTP Server\n(Axum)" as HTTP participant "Security\nMiddleware" as SEC participant "Component\nHandler" as HANDLER participant "Diagnostic\nKernel" as DIAG participant "UDS / DoIP" as COMM participant ECU Client -> HTTP : POST /components/{ecu} activate HTTP HTTP -> SEC : authenticate & authorize activate SEC SEC -> HTTP : OK deactivate SEC HTTP -> HANDLER : route to component handler activate HANDLER HANDLER -> DIAG : trigger variant detection activate DIAG DIAG -> DIAG : determine variant detection\nservices from MDD DIAG -> COMM : send UDS request(s)\nfor variant identification activate COMM COMM -> ECU : DoIP -> UDS request(s) activate ECU ECU -> COMM : response(s) deactivate ECU COMM -> DIAG : raw UDS response(s) deactivate COMM DIAG -> DIAG : evaluate responses against\nvariant patterns in MDD DIAG -> DIAG : select matching variant DIAG -> HANDLER : detected variant deactivate DIAG HANDLER -> HTTP : JSON body deactivate HANDLER HTTP -> Client : HTTP 200 OK\n{ variant information } deactivate HTTP @enduml