RFC 4757 has been reclassified as Historic. RFC 4757 Title: The RC4-HMAC Kerberos Encryption Types Used by Microsoft Windows Author: K. Jaganathan, L. Zhu, J. Brezak Status: Historic Stream: IETF Date: December 2006 Pages: 18 Characters: 36562 Updates/Obsoletes/SeeAlso: None I-D Tag: draft-jaganathan-rc4-hmac-03.txt URL: https://www.rfc-editor.org/info/rfc4757 DOI: 10.17487/RFC4757 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. HISTORIC: This memo defines a Historic Document for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. This announcement is sent to the IETF-Announce and rfc-dist lists. To subscribe or unsubscribe, see https://www.ietf.org/mailman/listinfo/ietf-announce https://mailman.rfc-editor.org/mailman/listinfo/rfc-dist For searching the RFC series, see https://www.rfc-editor.org/search For downloading RFCs, see https://www.rfc-editor.org/retrieve/bulk Requests for special distribution should be addressed to either the author of the RFC in question, or to rfc-editor@rfc-editor.org. Unless specifically noted otherwise on the RFC itself, all RFCs are for unlimited distribution. The RFC Editor Team Association Management Solutions, LLC