Connecting the SBC using Admin Center

Open “Microsoft Teams admin center”

On the menu on the left side of the portal, expand “Voice”

On the “Voice” menu, select “Direct Routing”

This will take you “Direct Routing” settings page

Click on “SBCs”

Click on the “Add” button

This will take you “Direct Routing\ Add SBC” page where you can define a new SBC with its settings

Type the name of your SBC

Under the SIP signaling port, the port number there is “5067”

I am changing the port to 5061. Which is the default port number that is usually created by the “Easy Setup” wizard of Ribbon SBC when you select the Direct Routing option

Under “Concurrent call capacity”, specify the number of channels you will select in “Easy Setup” wizard.

This number usually equals the maximum number of SIP sessions to your SIP provider.

Don’t forget to turn on the “Enabled” button

Click on the “Save” button at the end of the page

If you haven’t added the domain to Microsoft 365 and enabled a user under that domain, you will get a message similar to the one below

We can’t use the “sbc.domain.com” domain as it hasn’t been set up in the organization. Please try again. If you continue to have problems, contact Microsoft customer support.

As the image below shows

However, if everything is correct, you will get the message “Item was created” as the image below shows

The name of the newly registered SBC will be under the list of SBCs

Note:

The SBC would be shown to have errors because it is not yet configured to work with Direct Routing or the DNS record of type A that should point to its IP has not yet been created

Registering the SBC using PowerShell

Alternatively, you can register the SBC using New-CsOnlinePSTNGateway PowerShell command as the example below shows

New-CsOnlinePSTNGateway -Identity sbc1.jayslab.online -Enabled $true -SIPSignalingPort 5061 -MaxConcurrentSessions 4