Cisco documents that some ITSPs ignore the IP address and port in SDP because of their firewall design and send media only back to the source of RTP they first receive from the far end.

Checked 2026-09-24

Vendor
Cisco
Product
Cisco Unified Border Element
Subsystem
media
Deployment
on-premises
Region
not restricted
Release range
current as of 2026-09-24
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-latching-itsp. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-call-analysis-wireshark-cube-latching-itsp

BibTeX

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

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