Network Working Group J. Arkko
Request for Comments: 3830 E. Carrara
Category: Standards Track F. Lindholm
M. Naslund
K. Norrman
Ericsson Research
August 2004
MIKEY: Multimedia Internet KEYing
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2004).
Abstract
This document describes a key management scheme that can be used for
real-time applications (both for peer-to-peer communication and group
communication). In particular, its use to support the Secure Real-
time Transport Protocol is described in detail.
Security protocols for real-time multimedia applications have started
to appear. This has brought forward the need for a key management
solution to support these protocols.
Arkko, et al. Standards Track [Page 1]
RFC 3830 MIKEY August 2004
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Existing Solutions . . . . . . . . . . . . . . . . . . . 4
1.2. Notational Conventions . . . . . . . . . . . . . . . . . 4
1.3. Definitions. . . . . . . . . . . . . . . . . . . . . . . 4
1.4. Abbreviations. . . . . . . . . . . . . . . . . . . . . . 6
1.5. Outline. . . . . . . . . . . . . . . . . . . . . . . . . 6
2. Basic Overview . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1. Scenarios. . . . . . . . . . . . . . . . . . . . . . . . 7
2.2. Design Goals . . . . . . . . . . . . . . . . . . . . . . 8
2.3. System Overview. . . . . . . . . . . . . . . . . . . . . 8
2.4. Relation to GKMARCH. . . . . . . . . . . . . . . . . . . 10
3. Basic Key Transport and Exchange Methods . . . . . . . . . . . 10
3.1. Pre-shared Key . . . . . . . . . . . . . . . . . . . . . 12
3.2. Public-Key Encryption. . . . . . . . . . . . . . . . . . 13
3.3. Diffie-Hellman Key Exchange. . . . . . . . . . . . . . . 14
4. Selected Key Management Functions. . . . . . . . . . . . . . . 15
4.1. Key Calculation. . . . . . . . . . . . . . . . . . . . . 16
4.1.1. Assumptions. . . . . . . . . . . . . . . . . . . 16
4.1.2. Default PRF Description. . . . . . . . . . . . . 17
4.1.3. Generating keys from TGK . . . . . . . . . . . . 18
4.1.4. Generating keys for MIKEY Messages from
an Envelope/Pre-Shared Key . . . . . . . . . . . 19
4.2 Pre-defined Transforms and Timestamp Formats . . . . . . . 19
4.2.1. Hash Functions . . . . . . . . . . . . . . . . . 19
4.2.2. Pseudo-Random Number Generator and PRF . . . . . 20
4.2.3. Key Data Transport Encryption. . . . . . . . . . 20
4.2.4. MAC and Verification Message Function. . . . . . 21
4.2.5. Envelope Key Encryption. . . . . . . . . . . . . 21
4.2.6. Digital Signatures . . . . . . . . . . . . . . . 21
4.2.7. Diffie-Hellman Groups. . . . . . . . . . . . . . 21
4.2.8. Timestamps . . . . . . . . . . . . . . . . . . . 21
4.2.9. Adding New Parameters to MIKEY . . . . . . . . . 22
4.3. Certificates, Policies and Authorization . . . . . . . . 22
4.3.1. Certificate Handling . . . . . . . . . . . . . . 22
4.3.2. Authorization. . . . . . . . . . . . . . . . . . 23
4.3.3. Data Policies. . . . . . . . . . . . . . . . . . 24
4.4. Retrieving the Data SA . . . . . . . . . . . . . . . . . 24
4.5. TGK Re-Keying and CSB Updating . . . . . . . . . . . . . 25
5. Behavior and Message Handling. . . . . . . . . . . . . . . . . 26
5.1. General. . . . . . . . . . . . . . . . . . . . . . . . . 26
5.1.1. Capability Discovery . . . . . . . . . . . . . . 26
5.1.2. Error Handling . . . . . . . . . . . . . . . . . 27
5.2. Creating a Message . . . . . . . . . . . . . . . . . . . 28
5.3. Parsing a Message. . . . . . . . . . . . . . . . . . . . 29
5.4. Replay Handling and Timestamp Usage. . . . . . . . . . . 30
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