Twilio sends originating SIP requests over UDP by default, and a transport parameter such as ;transport=tcp or ;transport=tls on the origination URI selects another transport.

Checked 2026-09-24

By default, Twilio sends originating SIP requests towards your communications infrastructure over UDP.
Vendor
Twilio
Product
Elastic SIP Trunking
Subsystem
origination
Deployment
multi-tenant
Region
not restricted
Release range
current as of 2026-09-24
Checked
2026-09-24

Sources

Cite this note

APA

WarmTransfer. (2026, September 24). Setting up an Asterisk PBX with Twilio Elastic SIP Trunking: source note asterisk-twilio-pbx-setup-origination-default-udp. WarmTransfer. https://warmtransfer.net/knowledge/claims/asterisk-twilio-pbx-setup-origination-default-udp

BibTeX

@misc{warmtransfer-claim-asterisk-twilio-pbx-setup-origination-default-udp,
  title  = {Setting up an Asterisk PBX with Twilio Elastic SIP Trunking: source note asterisk-twilio-pbx-setup-origination-default-udp},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/claims/asterisk-twilio-pbx-setup-origination-default-udp},
  note   = {Source note asterisk-twilio-pbx-setup-origination-default-udp, checked 2026-09-24}
}

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