SRTP is a security profile for RTP that adds confidentiality, message authentication, and replay protection to that protocol. It is an action item in the IETF Audio-Video Transport Working Group, where it is an Internet Draft and is currently in IETF WG last call.
SRTP is ideal for protecting Voice over IP traffic because it can be used in conjunction with header compression and has no effect on IP Quality of Service. These facts provide significant advantages, especially for voice traffic using low-bitrate voice codecs such as G.729 and iLBC.
From the IETF RFC:
This document describes the Secure Real-time Transport Protocol
(SRTP), a profile of the Real-time Transport Protocol (RTP), which
can provide confidentiality, message authentication, and replay
protection to the RTP traffic and to the control traffic for RTP, the
Real-time Transport Control Protocol (RTCP).
(SRTP), a profile of the Real-time Transport Protocol (RTP), which
can provide confidentiality, message authentication, and replay
protection to the RTP traffic and to the control traffic for RTP, the
Real-time Transport Control Protocol (RTCP).
Devices and Clients known to utilize SRTP:
- PATTON Electronics 2-or-4 BRI Enterprise Session Border Controller with SRTP, the SmartNode 5530, will start shipping March 2015
- Sipura sometime during early realeses of their 2.x firmware
- pbxnsip supports SRTP and SDES/TLS
- CounterPath Bria and Asterisk phone eyeBeam softphones support SRTP and SDES/TLS
- snom phones phones support SRTP and SDES/TLS
- It seems that Cisco phones support SRTP (only skinny)
- InGate was one of the first firewalls supporting SRTP
- OpenWengo supports SRTP
- VegaStream supports SRTP adn SIP / TLS on its VoIP gateways
See also
- Asterisk SRTP
- RFC 3711
- Sipp – SIP UA for Linux that supports SRTP
- Asterisk encryption
September 17, 2011
Phone System 