RFC 4568 requires the SIP/SDP payload to be encrypted (for example with TLS) whenever it carries an inline SRTP master key, because an unencrypted key makes the SRTP protection useless.

Checked 2026-09-25

Failure to encrypt the SDP message containing an inline SRTP master key renders the SRTP authentication or encryption service useless in practically all circumstances.
Vendor
multi-vendor
Product
SDP security descriptions
Subsystem
SRTP keying
Deployment
any
Region
not restricted
Release range
RFC 4568
Checked
2026-09-25

Sources

Cite this note

APA

WarmTransfer. (2026, September 25). Setting up CUBE for a carrier SIP trunk: source note cube-carrier-trunk-setup-sdes-needs-encryption. WarmTransfer. https://warmtransfer.net/knowledge/claims/cube-carrier-trunk-setup-sdes-needs-encryption

BibTeX

@misc{warmtransfer-claim-cube-carrier-trunk-setup-sdes-needs-encryption,
  title  = {Setting up CUBE for a carrier SIP trunk: source note cube-carrier-trunk-setup-sdes-needs-encryption},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/cube-carrier-trunk-setup-sdes-needs-encryption},
  note   = {Source note cube-carrier-trunk-setup-sdes-needs-encryption, checked 2026-09-25}
}

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