What Is SRTP?
SRTP is the encrypted version of RTP, used in VoIP to prevent on-path eavesdropping. Pair it with TLS, which encrypts the SIP signaling.
Definition
SRTP (IETF RFC 3711) applies AES encryption at the media layer (RTP payload) plus an HMAC-SHA1 authentication tag to prevent in-transit tampering.
Usage
Used by organizations needing voice security, finance, healthcare, or PDPA / GDPR compliance, typically with TLS for end-to-end secure calls.
Related Concepts
Key exchange uses DTLS-SRTP (WebRTC), SDES (in SDP), or ZRTP, depending on implementation.
Frequently Asked Questions
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