ZyXEL Communications P-2302HWL-P1 Series - Manual (Page 183)

P-2302HW/HWL-P1 Series User’s Guide
Chapter 13 VoIP Trunking 183
Figure 96 VoIP to PSTN Example - Incoming Authentication
13.8.4 Call Progression
The advantage of this kind of VoIP trunking is that once all the configuration is completed, the
caller just has to dial a speed dial entry from a phone connected to their ZyXEL Device and the
peer devices take care of the rest. This is what happens when headquarters wants to call their
Sales1 employee, which is the first entry in the speed dial screen.
Table 77 VoIP Trunking Call Progression
HEADQUARTERS BRANCH OFFICE SALES1
A person at A dials #01 from the phone
connected to the ZyXEL Device.
The ZyXEL Device at A inspects the number and connects to the remote peer device at
B.
The remote peer device inspects the number and requests authentication in order to
forward the call.
The ZyXEL Device at A sends outgoing authentication to the remote peer device.
The remote peer device confirms that the username and password match an account in
its incoming authentication list.
The remote peer device forwards the call to Sales1.
Sales1 picks up and the call commences.