Source note · SIP registration failures
RFC 3261 requires a request larger than 1300 bytes, or within 200 bytes of the path MTU, to be sent over a congestion-controlled transport such as TCP rather than UDP.
Checked 2026-09-25
- Vendor
- not restricted
- Product
- SIP
- Subsystem
- transport
- Deployment
- any
- Region
- not restricted
- Release range
- RFC 3261
- Checked
- 2026-09-25
Sources
- RFC 3261 — SIP: Session Initiation Protocol — IETF / RFC Editor · tier 1 standards and regulators · Section 18.1.1 Sending Requests
Cite this note
APA
WarmTransfer. (2026, September 25). SIP registration failures: source note sip-registration-failures-udp-1300-bytes. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-registration-failures-udp-1300-bytes
BibTeX
@misc{warmtransfer-claim-sip-registration-failures-udp-1300-bytes,
title = {SIP registration failures: source note sip-registration-failures-udp-1300-bytes},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-registration-failures-udp-1300-bytes},
note = {Source note sip-registration-failures-udp-1300-bytes, checked 2026-09-25}
}