The firewall in front of Asterisk likely needs to admit UDP from Twilio's 168.86.128.0/18 media range to Asterisk's own rtpstart-rtpend range, since Twilio requires its media ranges allowed and Asterisk receives RTP only on that range.

inferred · Checked 2026-09-24

Vendor
Sangoma
Product
Asterisk
Subsystem
network
Deployment
self-hosted
Region
not restricted
Release range
current as of 2026-09-24
Status
inferred
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-firewall-rtp-pairing. WarmTransfer. https://warmtransfer.net/knowledge/claims/asterisk-twilio-pbx-setup-firewall-rtp-pairing

BibTeX

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

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