RFC 2403 · PROPOSED STANDARD · 1998
SUN · 14 JUN 2026
The Use of HMAC-MD5-96 within ESP and AH
Overview
RFC 2403, “The Use of HMAC-MD5-96 within ESP and AH”, is a Proposed Standard document published in November 1998 by C. Madson, R. Glenn. The canonical text is published by the RFC Editor.
Abstract
This memo describes the use of the HMAC algorithm in conjunction with the MD5 algorithm as an authentication mechanism within the revised IPSEC Encapsulating Security Payload and the revised IPSEC Authentication Header. [STANDARDS-TRACK]
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 2403 is hosted at rfc-editor.org. Available in TXT,HTML.
Other RFCs from 1998
- RFC 2402 IP Authentication Header
- RFC 2404 The Use of HMAC-SHA-1-96 within ESP and AH
- RFC 2401 Security Architecture for the Internet Protocol
- RFC 2405 The ESP DES-CBC Cipher Algorithm With Explicit IV
- RFC 2400 Internet Official Protocol Standards
- RFC 2406 IP Encapsulating Security Payload
- RFC 2407 The Internet IP Security Domain of Interpretation for ISAKMP
- RFC 2398 Some Testing Tools for TCP Implementors