Datagram Transport Layer Security (DTLS) Extension to Establish Keys for the Secure Real-time Transport Protocol (SRTP)
RFC 5764
Document | Type |
RFC - Proposed Standard
(May 2010; Errata)
Updated by RFC 7983
|
|
---|---|---|---|
Authors | David McGrew , Eric Rescorla | ||
Last updated | 2020-01-21 | ||
Replaces | draft-mcgrew-tls-srtp | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Reviews | |||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 5764 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Cullen Jennings | ||
Send notices to | (None) |
Internet Engineering Task Force (IETF) D. McGrew Request for Comments: 5764 Cisco Systems Category: Standards Track E. Rescorla ISSN: 2070-1721 RTFM, Inc. May 2010 Datagram Transport Layer Security (DTLS) Extension to Establish Keys for the Secure Real-time Transport Protocol (SRTP) Abstract This document describes a Datagram Transport Layer Security (DTLS) extension to establish keys for Secure RTP (SRTP) and Secure RTP Control Protocol (SRTCP) flows. DTLS keying happens on the media path, independent of any out-of-band signalling channel present. Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc5764. Copyright Notice Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. McGrew & Rescorla Standards Track [Page 1] RFC 5764 SRTP Extension for DTLS May 2010 This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions Used In This Document . . . . . . . . . . . . . . 3 3. Overview of DTLS-SRTP Operation . . . . . . . . . . . . . . . 4 4. DTLS Extensions for SRTP Key Establishment . . . . . . . . . . 5 4.1. The use_srtp Extension . . . . . . . . . . . . . . . . . . 5 4.1.1. use_srtp Extension Definition . . . . . . . . . . . . 7 4.1.2. SRTP Protection Profiles . . . . . . . . . . . . . . . 8 4.1.3. srtp_mki value . . . . . . . . . . . . . . . . . . . . 9 4.2. Key Derivation . . . . . . . . . . . . . . . . . . . . . . 10 4.3. Key Scope . . . . . . . . . . . . . . . . . . . . . . . . 12 4.4. Key Usage Limitations . . . . . . . . . . . . . . . . . . 12 5. Use of RTP and RTCP over a DTLS-SRTP Channel . . . . . . . . . 13 5.1. Data Protection . . . . . . . . . . . . . . . . . . . . . 13 5.1.1. Transmission . . . . . . . . . . . . . . . . . . . . . 13 5.1.2. Reception . . . . . . . . . . . . . . . . . . . . . . 13 5.2. Rehandshake and Rekey . . . . . . . . . . . . . . . . . . 16 6. Multi-Party RTP Sessions . . . . . . . . . . . . . . . . . . . 17 7. Security Considerations . . . . . . . . . . . . . . . . . . . 17 7.1. Security of Negotiation . . . . . . . . . . . . . . . . . 17 7.2. Framing Confusion . . . . . . . . . . . . . . . . . . . . 17 7.3. Sequence Number Interactions . . . . . . . . . . . . . . . 18 7.3.1. Alerts . . . . . . . . . . . . . . . . . . . . . . . . 18 7.3.2. Renegotiation . . . . . . . . . . . . . . . . . . . . 18 7.4. Decryption Cost . . . . . . . . . . . . . . . . . . . . . 19 8. Session Description for RTP/SAVP over DTLS . . . . . . . . . . 19 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20 10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 21Show full document text