ZyXEL p-2302hw-p1 Manual Do Utilizador

P-2302HW/HWL-P1 Series User’s Guide

Chapter 13 VoIP Trunking

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Use these screens to configure VoIP trunking on your ZyXEL Device. 

VoIP trunking connects an IP network (like the Internet) and the Public Switched Telephone 
Network (PSTN). PSTN includes the world’s circuit-switched telephone network which is 
composed of fixed and mobile telephones. VoIP trunking allows you to create VoIP links 
which PSTN (Public Switched Telephone Network) callers can use to:

• Make phone calls via the Internet - Make a PSTN call to the ZyXEL Device and it 

forwards the call to any SIP based VoIP phone.

• Save on long distance calls - The ZyXEL Device creates a VoIP link which can be used to 

connect to a PSTN phone in another country, province, region and so on. 

Similarly, VoIP callers can:

• Make calls to PSTN subscribers at reduced cost - Connect to the ZyXEL Device via VoIP 

and the ZyXEL Device forwards the call to a PSTN phone.

Creating a link over the IP network requires two VoIP devices. VoIP trunking scenarios vary 
depending on how the VoIP devices work together and how they receive or forward PSTN 
calls. The following sections describe the details of VoIP trunking.

Your ZyXEL Device provides two types of authentication to prevent unauthorized callers from 
using it for VoIP trunking.

Auto attendant is the ZyXEL Device’s name for a service which controls settings specific to 
VoIP trunking. Most importantly it controls authentication for VoIP trunking. Auto attendant 
authentication is similar to using a calling card with a PIN (Personal Identification Number). 
Your ZyXEL Device can be configured so that it prompts callers to enter a PIN (via the phone 
pad) in order to process any call forwarding requests.