Configure the properties of a Gmail domain

When you add or edit a Gmail domain, you configure its properties.

In the Name box, type the name of your Gmail domain.
In the Default sender box, type any email account in your domain. When an external caller leaves you a message, this is the email account that appears as the "From" address in the interaction.
Click Load JSON. This loads the JSON file that you generated from the Google Developer Console in your Gmail account.
Click OK.