By combining the three values found in the found in the AFI, ASF and the AUS, a user can send a message from most a digit-only-based origination agent to a user who may be using most any agent.
Let's look at some examples. An originator calls me and connects to the Neda IVR system. They can originate an email message to 320664480261. Since the AFI is 3, the system knows that there will be 10 digits containing the North American Numbering Plan phone number of the recipient. The final digit is the AUS. Since the value is 1, the system knows that it should deliver the message to my e-mail box. By simply changing the last digit to a 2 (so the TO: address would be 320664480262), the system would know to deliver the message to my fax machine.
In this second example, let's suppose that the sender knows that I am a subscriber of Neda Services. I have told them that my Neda identification number is 201-666. The originator again calls me and connects to the Neda IVR system. The the sender would know that I'm not at my desk, but may not know if I'm even in town. The sender can enter a message and address it to 12016660. The one in the AFI spot indicates to the system that the next 6 digits will specify the Neda subscriber. The zero in the MBS spot allows the system to determine which mail box I have identified as my current default mailbox and deliver the message to that mailbox.