Options for Securing RTP Sessions
RFC 7201
Internet Engineering Task Force (IETF) M. Westerlund
Request for Comments: 7201 Ericsson
Category: Informational C. Perkins
ISSN: 2070-1721 University of Glasgow
April 2014
Options for Securing RTP Sessions
Abstract
The Real-time Transport Protocol (RTP) is used in a large number of
different application domains and environments. This heterogeneity
implies that different security mechanisms are needed to provide
services such as confidentiality, integrity, and source
authentication of RTP and RTP Control Protocol (RTCP) packets
suitable for the various environments. The range of solutions makes
it difficult for RTP-based application developers to pick the most
suitable mechanism. This document provides an overview of a number
of security solutions for RTP and gives guidance for developers on
how to choose the appropriate security mechanism.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
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). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see 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/rfc7201.
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RFC 7201 Options for Securing RTP Sessions April 2014
Copyright Notice
Copyright (c) 2014 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
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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.
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RFC 7201 Options for Securing RTP Sessions April 2014
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Background . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Point-to-Point Sessions . . . . . . . . . . . . . . . . . 5
2.2. Sessions Using an RTP Mixer . . . . . . . . . . . . . . . 5
2.3. Sessions Using an RTP Translator . . . . . . . . . . . . 6
2.3.1. Transport Translator (Relay) . . . . . . . . . . . . 6
2.3.2. Gateway . . . . . . . . . . . . . . . . . . . . . . . 7
2.3.3. Media Transcoder . . . . . . . . . . . . . . . . . . 8
2.4. Any Source Multicast . . . . . . . . . . . . . . . . . . 8
2.5. Source-Specific Multicast . . . . . . . . . . . . . . . . 8
3. Security Options . . . . . . . . . . . . . . . . . . . . . . 10
3.1. Secure RTP . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.1. Key Management for SRTP: DTLS-SRTP . . . . . . . . . 12
3.1.2. Key Management for SRTP: MIKEY . . . . . . . . . . . 14
3.1.3. Key Management for SRTP: Security Descriptions . . . 15
3.1.4. Key Management for SRTP: Encrypted Key Transport . . 16
3.1.5. Key Management for SRTP: ZRTP and Other Solutions . . 17
3.2. RTP Legacy Confidentiality . . . . . . . . . . . . . . . 17
3.3. IPsec . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.4. RTP over TLS over TCP . . . . . . . . . . . . . . . . . . 18
3.5. RTP over Datagram TLS (DTLS) . . . . . . . . . . . . . . 18
3.6. Media Content Security/Digital Rights Management . . . . 19
3.6.1. ISMA Encryption and Authentication . . . . . . . . . 19
4. Securing RTP Applications . . . . . . . . . . . . . . . . . . 20
4.1. Application Requirements . . . . . . . . . . . . . . . . 20
4.1.1. Confidentiality . . . . . . . . . . . . . . . . . . . 20
4.1.2. Integrity . . . . . . . . . . . . . . . . . . . . . . 21
4.1.3. Source Authentication . . . . . . . . . . . . . . . . 22
4.1.4. Identifiers and Identity . . . . . . . . . . . . . . 23
4.1.5. Privacy . . . . . . . . . . . . . . . . . . . . . . . 24
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