The SDP a=crypto attribute carries SRTP keying material, and RFC 4568 requires the SDP carrying it to be protected by S/MIME or a lower-layer service such as TLS or IPsec.

Checked 2026-09-24

Vendor
IETF
Product
SDES
Subsystem
a=crypto
Deployment
multi-tenant, on-premises
Region
not restricted
Release range
RFC 4568
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Analysing a SIP call in Wireshark: source note sip-call-analysis-wireshark-sdes-needs-secure-sig. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-call-analysis-wireshark-sdes-needs-secure-sig

BibTeX

@misc{warmtransfer-claim-sip-call-analysis-wireshark-sdes-needs-secure-sig,
  title  = {Analysing a SIP call in Wireshark: source note sip-call-analysis-wireshark-sdes-needs-secure-sig},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-call-analysis-wireshark-sdes-needs-secure-sig},
  note   = {Source note sip-call-analysis-wireshark-sdes-needs-secure-sig, checked 2026-09-24}
}

Read in context