RFC 8085 (BCP 145) says applications SHOULD NOT send UDP datagrams that result in IP packets exceeding the MTU along the path.

Checked 2026-10-02

Vendor
not restricted
Product
not restricted
Subsystem
UDP message sizing
Deployment
on-premises, multi-tenant
Region
not restricted
Release range
BCP 145 as published
Checked
2026-10-02

Sources

Cite this note

APA

WarmTransfer. (2026, October 2). Troubleshooting failed calls caused by large SIP messages over UDP: source note sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu

BibTeX

@misc{warmtransfer-claim-sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu,
  title  = {Troubleshooting failed calls caused by large SIP messages over UDP: source note sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu},
  note   = {Source note sip-fragmentation-troubleshooting-rfc8085-no-exceed-path-mtu, checked 2026-10-02}
}

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