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Feature Release: SIP Subdomains for Inbound Calls

New Feature Release: SIP Subdomain

We’re excited to announce a new feature release for inbound calls called SIP Subdomains. SIP Subdomain is now available in the Mission Control Portal and Telnyx API.

SIP Subdomain provides the ability to receive VoIP calls to your business numbers via Telnyx’s purpose-built, private IP network, without having to port your numbers into the Telnyx network.

Specify a subdomain that can be used to receive Inbound calls to a Connection, in the same way a phone number is used, from a SIP endpoint. By default this option is enabled to receive calls from any SIP endpoint on the Internet without the need for authentication.


How to set up?

  1. Sign into the Telnyx Mission Control Portal.
  2. Click on Connections in the navigation menu on the left-hand side of the portal.
  3. Click the “Basic Options” button [✎] for the connection you want to modify.
    Note: Connections type Credential Authentication are not allowed to have a SIP Subdomain, please use SIP URI calls instead.
  4. Specify your SIP subdomain.
  5. Save your changes.
That’s it. You’re all set to start using SIP subdomain.

How does it work?

SIP Subdomains are similar to SIP URIs. However, SIP URIs can only be assigned to connections with credential authentication, while SIP Subdomains are allowed for any other Connection type.

When Telnyx receives SIP calls to your subdomain over the public internet, they will be routed to your connection.

The SIP username part of the Request URI isn’t considered by Telnyx and can also be non-existent.

Example SIP Subdomain: companyA.sip.telnyx.com
You will now receive calls for:
  • companyA.sip.telnyx.com
  • john@companyA.sip.telnyx.com
  • 1234567890@companyA.sip.telnyx.com
Note: SIP TLS encrypted calls are not allowed for SIP Subdomains.

What are the benefits?

SIP subdomains offer several benefits:
  • You don’t need to port your phone numbers to the Telnyx network. You can set up connections to receive VoIP calls on a number existing on an outside network.
  • You don’t need a phone number. You can receive calls on your subdomain, which means you can reach all of your Telnyx accounts without attaching a phone number.
  • It’s cost-effective. The call receiver pays $.002/minute for a SIP Subdomain call vs. a traditional inbound voice call charged at $0.0075/minute.
  • You don’t need to reveal your phone number, which offers you more privacy and security. It's just like giving out your email address.
  • Anyone without a phone number can reach you if they have a SIP device and internet access.

To use our SIP subdomain feature, head to the Mission Control Portal.

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