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Documentation Index

Fetch the complete documentation index at: https://docs.astradial.com/llms.txt

Use this file to discover all available pages before exploring further.

A SIP trunk is the connection between Astradial and a phone carrier (like Tata, Airtel, Twilio, or any SIP provider). Without a trunk, you can make calls between extensions inside Astradial, but you cannot call real phone numbers or receive calls from the outside world.

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What is a SIP trunk?

Think of a SIP trunk like a phone line connecting your office phone system to the telephone network. It is the bridge between your internet-based phone system and the real phone network.
TermMeaning
Inbound trunkReceives calls from the phone network into Astradial
Outbound trunkSends calls from Astradial out to phone numbers
Peer-to-peerBoth inbound and outbound on the same connection

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View your trunks

Go to Trunks in the sidebar under Deploy. You will see a table showing all configured trunks with:
  • Name — A label you gave the trunk
  • Host — The SIP server address and port
  • Type — Inbound, Outbound, or Peer-to-peer
  • Transport — UDP, TCP, or TLS
  • Channels — Maximum simultaneous calls allowed
  • Registration — Whether the trunk is successfully connected to the carrier
  • Status — Active or Inactive

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Create a trunk

Only admins and owners can create trunks.
1

Click Add Trunk

Click the Add Trunk button (plus icon). Only visible to admins.
2

Fill in the connection details

FieldWhat to enterExample
NameA label for this trunkTata SIP
HostThe carrier’s SIP server addresssip.provider.com
PortSIP port (usually 5060)5060
TransportUDP, TCP, or TLSUDP
TypeInbound, Outbound, or Peer-to-PeerOutbound
UsernameSIP authentication usernameyour_sip_user
PasswordSIP authentication passwordyour_sip_pass
Max ChannelsHow many simultaneous calls10
3

Click Create

Astradial creates the trunk and registers it with the carrier. Check the Registration column — it should show “registered” within a few seconds.

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Registration status

StatusMeaning
RegisteredThe trunk is connected and ready for calls
UnregisteredThe trunk is not connected — check credentials or network
FailedThe registration attempt failed — verify host, username, and password

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Edit a trunk

  1. Click the three-dot menu next to the trunk
  2. Click Edit
  3. Update any field (leave password blank to keep the current one)
  4. Click Save

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Delete a trunk

  1. Click the three-dot menu next to the trunk
  2. Click Delete
  3. Confirm the deletion
Deleting a trunk disconnects all phone numbers that use it. Make sure to reassign your phone numbers to a different trunk first.

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Get a free developer trunk

If you need a trunk for testing, click the Request Free Trunk button at the bottom of the page. This sends an email to the Astradial team to set up a free developer trunk with 1 channel and 1 Indian DID for 30 days.