DNIS lets you know which phone number your customer called to reach you and is useful in a variety of circumstances. For example, if you're operating a call center, you could set up your switch to recognize the DNIS of an incoming call and play the appropriate greeting for the product associated with the toll-free number.
To create the DNIS information for a toll-free number:
Control Center displays a list of all services assigned to the accounts under your enterprise ID. If you have more than ten services, you can view the rest of your services by clicking one of the blue linked Show numbers at the top of the list or you can click the blue down arrow at the bottom of the list to add ten services at a time to the view.