Source note · One-way and no-way audio diagnosis
Technote 214622 attributes the hairpin deadlock to ITSPs that ignore the SDP media address because of firewall restrictions and wait to receive RTP first. That leaves CUBE needing to send RTP first.
Checked 2026-09-24
- Vendor
- Cisco
- Product
- Cisco Unified Border Element
- Subsystem
- hairpin media
- Deployment
- on-premises
- Region
- not restricted
- Release range
- technote 214622
- Checked
- 2026-09-24
Sources
- Troubleshoot No-way Audio Issue with Hairpin Calls on CUBE — Cisco Systems, Inc. (www.cisco.com) · tier 2 current vendor documentation · Technote 214622, Problem section
Cite this note
APA
WarmTransfer. (2026, September 24). One-way and no-way audio diagnosis: source note one-way-audio-hairpin-itsp-firewall. WarmTransfer. https://warmtransfer.net/knowledge/claims/one-way-audio-hairpin-itsp-firewall
BibTeX
@misc{warmtransfer-claim-one-way-audio-hairpin-itsp-firewall,
title = {One-way and no-way audio diagnosis: source note one-way-audio-hairpin-itsp-firewall},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/one-way-audio-hairpin-itsp-firewall},
note = {Source note one-way-audio-hairpin-itsp-firewall, checked 2026-09-24}
}