Domain is simply a technical term used to logically group a bunch of stuff together. In this example, two domains are available. You may have one or more to choose from.
The domain highlighted green is the one that you are viewing the console for - in this instance omniis.
In babblevoice, under a domain you have a bunch of phones, call rules and users who have access to manage these items and other stuff.
Typically a domain is used to represent a business’s phone system.
A business might however, decide to have several different babblevoice domains representing different parts of their business.
In surgery speak, it would probably represent a surgery and maybe a branch surgery. Some organisations group more surgeries together into one domain. The choice is yours.
More detailed information on your domain settings can be viewed here.
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