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Set Up IP-based Authentication for Outbound Calls

If your phone system has a Static IP address[1], we recommend using IP-based authentication for your outbound call authorization.

Before you begin

Have the following information ready before setting up IP-based authentication:

  • Your Flowroute Tech Prefix found on your Account Profile page. 

  • A list of IP addresses prepared to set up IP-based authentication

To set up IP-based authentication:
  1. On your PBX phone server, configure your Flowroute Outbound Route to use the following outbound dialing format:


    XXXXXXXX is your account Tech Prefix—for example, 12345678—followed by an asterisk (*), and  

    1NPANXXXXXX is the number to dial. The chosen number should be formatted first with the country code 1 (for North America), followed by the three-digit area code, NPA, and then the phone number, NXXXXXX.  For example, 12066418000

[preferred_PoP] - your preferred PoP you can select here

Your dial string should then resemble the following: 

Then go to the Interconnection > Outbound Allowed IPs page on your Flowroute account.  

    In the Enter IP Address field, enter your system's Public IP address(s)[2]. Click Add IP Address

  2. Follow the steps for statically routing your inbound calls to your Public IP Address.

Repeat the steps above for each PBX phone system that you are using.

IMPORTANT: For your security, we recommend using IP-based authentication exclusively by disabling SIP credentials for outbound calls in Flowroute Manage. This change will restrict outbound calls on your account to complete only from your Outbound Allowed IPs. To make this change, go to Flowroute Manage. In the top section of this page, click Disable Credentials.

[1] If your phone system uses a dynamic IP address, you'll need to use SIP Credential Authentication to authorize your outbound calls. This is the default authentication method supported by most PBX/switch builds.

[2] If you will be using IP-based authentication for outbound calls from multiple phone systems, you must make sure to enter each system's public IP address on the Outbound Allowed IPs page for your account.