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Rohit001's avatar
Rohit001
Copper Contributor
Sep 15, 2022

Microsoft teams Direct routing Carrier model

We are using Microsoft 365 teams direct routing carrier model.

We have our carrier trunk in carrier domain which is working fine, the TLS connection is active and option messages are being exchanged.

the carrier trunk is with domain "@customers.veeno.in

Now in the second stage when we moved to tenant configuration, the Microsoft documentation says below :

Sbc1.customers.adatum.biz – the derived trunk in a customer tenant. You can add the name of the derived trunk in the customer tenant in the voice routes without creating it.

IN our scenario, the tenant subdomain for SIP trunk is "ameyo.customers.veeno.in" but i can not find an option to add it directly in the voice routes unless and until I create a SIP trunk

But the problem is upon creating a SIP trunk in Tenant , the TLS connection remains inactive and option messages are also not being exchanged.  Please help

 

  • ECPTA's avatar
    ECPTA
    Copper Contributor

    Rohit001 hi, yes, it's a bit tricky at first. Regarding the derived trunk. However, once you see how easy it is. It is actually quite straight forward. You do not create SIP trunk. Delete that if you have done so. That is for when you have your own SBC. Or you connect to an ISP whose hosting one, not using derived method. All you need to do. Is create those DNS records (add the domain in your tenant). Which you have done. 

     

    Then create voice routes. I used Powershell to do this. You simply point the voice route to the DNS and it should work. That is all you need to do. 

    • ECPTA's avatar
      ECPTA
      Copper Contributor
      So, the entire process...

      Before you can add the Voice Routes, you need to add the tenant-specific sub-domain to the your Office 365 tenant, as an additional domain.

      EG:

      Carrier: sbc.voiceisp.com

      You: contoso.sbc.voiceisp.com



      Once the sub-domain is added for your tenant & the TXT record to the carrier's DNS to authorise the sub-domain addition, you then create a dummy user within the new domain, with a Teams license.

      EG:

      email address removed for privacy reasons
      - licensed with E3/E5 etc.



      The license only needs to be assigned for 30/60 minutes while the platform activates the domain. You can free it up once it has completed.

      Following this, you should then be able to create the voice routes etc. Just add voice route or I prefer through Powershell. Point it to constoso.sbc.voiceisp.com and it should start working.
      • Rohit001's avatar
        Rohit001
        Copper Contributor
        We have got everything working..
        We have a very simple setup for Microsoft Teams direct routing. Everything is working fine with incoming and outgoing calls.

        We are facing problems after implementing LBR. I am stating a problem as it is with respect to the setup we have.


        We have users who are sitting in the office , using team applications on their PCs and were able to make and receive calls.

        Now we have implemented LBR to restrict these users to make calls when they are not connected to the office network or restrict when they are trying to make calls from any network except the office.

        Now in the office the private network is 192.168/168.0/24 and public IP is X.X.X.X/27.

        I have defined the private subnet in the network topology subnet And public IP's in the trusted IPs list.. So , ideally the call should work when users are trying from the office network. But the problem is calls are not working even from the office network which should be allowed as per the LBR.

        Users are getting error : calls failing with Get Outbound Direct routing - no trunk config found by LBR selection criteria.


  • Faisal1775's avatar
    Faisal1775
    Brass Contributor

    Rohit001 

    Microsoft Teams Direct Routing is a feature that allows organizations to use their existing telephony infrastructure to make and receive calls in Microsoft Teams.

    The carrier model of Direct Routing involves using a third-party telecommunications carrier to provide the necessary connectivity between the public switched telephone network (PSTN) and Microsoft Teams. This model is ideal for organizations that want to use their own SIP trunks and have the expertise to manage their own carrier relationships.

    In this model, the organization works with a Direct Routing partner who will provide a connection between the organization's SIP trunk and Microsoft Teams. The partner will handle the configuration and management of the connection, as well as provide support for any issues that arise.

    To set up Direct Routing with the carrier model, you will need to work with a certified Direct Routing partner and configure your telephony infrastructure to support the necessary connectivity to Microsoft Teams. The partner will help you configure your Session Border Controllers (SBCs) and provide guidance on any required network changes.

    Once the setup is complete, users in your organization can make and receive calls in Microsoft Teams using your existing telephony infrastructure. This can help streamline communication and improve productivity by enabling users to easily switch between messaging, video conferencing, and phone calls all in one platform.

    • Rohit001's avatar
      Rohit001
      Copper Contributor
      THe setup is working absolutely fine. THe problem with implementing an LBR, when i implement LBR no calls work

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