Cisco documents intermittent one-way audio with some ITSPs whose equipment does not accept SDP carrying both a session-level and a media-level c= line, although the SDP specification permits it.

Checked 2026-09-24

Vendor
Cisco
Product
Cisco Unified Border Element
Subsystem
SDP
Deployment
on-premises
Region
not restricted
Release range
as published 2013-04-26
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-cube-dup-c-lines. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-call-analysis-wireshark-cube-dup-c-lines

BibTeX

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

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