RFC 8573 · PROPOSED STANDARD · 2019

Message Authentication Code for the Network Time Protocol

Overview

RFC 8573, “Message Authentication Code for the Network Time Protocol”, is a Proposed Standard document published in June 2019 by A. Malhotra, S. Goldberg. It updates RFC 5905. It has since been updated by RFC 9748. The canonical text is published by the RFC Editor.

Abstract

The Network Time Protocol (NTP), as described in RFC 5905, states that NTP packets should be authenticated by appending NTP data to a 128-bit key and hashing the result with MD5 to obtain a 128-bit tag. This document deprecates MD5-based authentication, which is considered too weak, and recommends the use of AES-CMAC as described in RFC 4493 as a replacement.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 8573 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 5905
Updated by
RFC 9748
Other RFCs from 2019

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