---
title: RADIUS messages
sidebar_custom_props:
    termName: RADIUS messages
    tags:
        - Protocols
    shortDescription: Access‑Request/Accept/Reject and Accounting messages.
    longDescription: Core flow - NAS sends Access‑Request; server replies Access‑Accept (optionally with attributes) or Access‑Reject. Accounting‑Start/Stop records session usage.
---
