# Automotive security terms, explained by the people who test ECUs.

> The AutoST glossary defines terms from vehicle diagnostics and automotive cybersecurity: UDS services and negative response codes, data and routine identifiers, SecurityAccess, ISO-TP, CAN and CAN FD, DoIP, SOME/IP, ODX and CDD, TARA, CAL, CSMS, ISO/SAE 21434 and UN R155. Every entry names its source.

Plain definitions of automotive cybersecurity terms: UDS services, DIDs, NRCs, SecurityAccess, DoIP, SOME/IP, ODX, TARA, ISO/SAE 21434 and UN R155. Each with its source.

Source: https://auto-st.com/glossary

Each entry says in a few sentences what a term means, where it is defined and how it shows up on a real ECU. Written by the AutoST team, checked against ISO 14229, ISO 13400 and ISO/SAE 21434.

## From ADB to UN R156

## Definitions from the standard, plus what the bench shows

Diagnostics vocabulary is precise in the standards and loose in daily use. We define each term the way ISO 14229, ISO 13400 or ISO/SAE 21434 does, cite the clause and then add what we see on real ECUs: how the term appears in a trace, what typically goes wrong and how AutoST tests it.

Entries link to the related guides, comparisons and tools. If a term is missing, tell us and we add it.

## FAQ

**Who writes the entries?**

The AutoST team at Zyberum, the same engineers who do ECU and vehicle penetration tests. Every entry is checked against the standard it cites and carries the date of its last update.

**Can I link to or quote an entry?**

Yes. Each entry has a stable URL and a Markdown copy. Quote with a link to the page. For reuse beyond a quotation, ask us.

**Why mix diagnostics terms with regulation?**

Because that is how ECU security work happens: a SecurityAccess weakness found on the bench becomes a threat scenario in the TARA and evidence in the UN R155 audit. The entries connect both sides.

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AutoST by Zyberum. Canonical page: https://auto-st.com/glossary