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Click on an existing group/department to edit that group (mainly for existing customers) or create a new group/department (for new customers or if an existing customer wishes to re-configure their permissions)
The Toll Restriction box displays all of the dial plans that you have already created. Treat these dial plans like a permission for the group. If you add the dial plan to the Current Dial Plans area, all the members of the group you are editing will be able to make calls matching the dial plan(s) permitted.
Ctrl + Click (or Command + Click on Mac!) multiple dial plans from the Available Dial Plans area and then click Add to move them to the right.
Click Update Group at the bottom of the page to apply your settings.
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You work at a Law Office. All day long clients visit the office to conduct business. In the waiting area of your office, you want to provide a curteousy courtesy phone for waiting clients. You aren't trying to give the clients cart blanche to call anyone they like - only local calls or perhaps domestic long distance (if it's free to you - why not?). So you could create a group called "Lobby Phone" and only add the lobby phone as a user. Then you would set the Toll Restriction to local and domestic long distance strings only. This prevents customers in your waiting area from making international calls on your dime.