Cisco's BroadWorks note states Polycom phones can be set to TCPOnly, TCPpreferred or DNSnaptr transport so large SIP messages avoid UDP.
Checked 2026-10-02
- Vendor
- Poly
- Product
- Poly UC Software
- Subsystem
- SIP transport
- Deployment
- on-premises
- Region
- not restricted
- Release range
- as of 2020-11-11 Cisco document update
- Checked
- 2026-10-02
Sources
- Working with large SIP packets — Cisco Systems · tier 2 current vendor documentation · Endpoints and SBCs section
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting failed calls caused by large SIP messages over UDP: source note sip-fragmentation-troubleshooting-poly-tcppreferred-option. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-fragmentation-troubleshooting-poly-tcppreferred-option
BibTeX
@misc{warmtransfer-claim-sip-fragmentation-troubleshooting-poly-tcppreferred-option,
title = {Troubleshooting failed calls caused by large SIP messages over UDP: source note sip-fragmentation-troubleshooting-poly-tcppreferred-option},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-fragmentation-troubleshooting-poly-tcppreferred-option},
note = {Source note sip-fragmentation-troubleshooting-poly-tcppreferred-option, checked 2026-10-02}
}