Utilizing VoIP Account to Deliver DID number for TB ISDN Gateway


TB is interconnected with a PBX which only supports to register VoIP trunk from other device. TB could provide a VoIP account to the PBX. But the limitation is TB can only send the DID of its account number rather than other DID numbers. Therefore we offer a solution to achieve this goal.

A general call flow: Caller -- ISDN Line --> TB -- SIP --> PBX --> Extension

Scope of application: this guide is suitable for TB Firmware version -; other version, please check with our support.


Here is the procedure:

1. Configure the DID Number and DID Associated Number field with a single number association or a range association.

In this figure, if you dial 5503301 from ISDN line, TB will try to deliver DID 6001 via Account1.

In this figure, if you dial one DID number within the range 5503301-5503305 from ISDN line, TB will try to deliver corresponding DID 6001-6005 via Account1.

 2. Enter the SSH interface by following this guide: Enter SSH

 3. Copy the content under context [globals]. Access the extensions.conf by command:

vi /etc/asterisk/extensions.conf

If you don't know how the customization for configuration file works, you can access this guide: User-Defined-Configuration-Modification

Note: because the content includes the global parameters, so before you go ahead; please ensure all your general settings are configured and all SIP trunks are created.

4. Create extensions_custom.conf in the path /persistent/custom-cfg/ by command:

vi /persistent/custom-cfg/extensions_custom.conf

Paste the content from Step 3 into this file. And modify the line related with Account1. Pay attention to the sign ";". This is to make the line invalid. After modification, save this file.

5. Save and Apply any changes on the web or reboot TB to make the modification take effect.

6.Test if it works.


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