RFC 4757 · HISTORIC · 2006

The RC4-HMAC Kerberos Encryption Types Used by Microsoft Windows

Overview

RFC 4757, “The RC4-HMAC Kerberos Encryption Types Used by Microsoft Windows”, is a Historic document published in December 2006 by K. Jaganathan, L. Zhu, J. Brezak. It has since been updated by RFC 6649. The canonical text is published by the RFC Editor.

Abstract

The Microsoft Windows 2000 implementation of Kerberos introduces a new encryption type based on the RC4 encryption algorithm and using an MD5 HMAC for checksum. This is offered as an alternative to using the existing DES-based encryption types.

The RC4-HMAC encryption types are used to ease upgrade of existing Windows NT environments, provide strong cryptography (128-bit key lengths), and provide exportable (meet United States government export restriction requirements) encryption. This document describes the implementation of those encryption types. This memo provides information for the Internet community.

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

What “Historic” means

A specification that has been superseded or is otherwise no longer recommended for use.

Read this RFC

The canonical text of RFC 4757 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Updated by
RFC 6649
Other RFCs from 2006

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