ZyXEL Communications prestige p-2002 User Manual

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P-2002 Series User’s Guide
Chapter 1 Introducing the Prestige
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Figure 2   Internet Telephony Service Provider Application
1.5.2  Make Calls via IP-PBX
If your company has an IP-PBX (Internet Protocol Private Branch Exchange), you can use the 
Prestige to make and receive VoIP telephone calls through it.
In this example, you use your analog phone (A in the figure) and the Prestige (B) changes the 
call into VoIP and sends it to the IP-PBX. The IP-PBX forwards calls to PSTN phones (C) to 
the PSTN network. The IP-PBX forwards calls to IP phones (D) through an IP network (this 
could include the Internet).
Figure 3    IP-PBX Application
1.5.3  Make Peer-to-peer Calls
Use the Prestige to make a call to the recipient’s IP address without using a SIP proxy server 
Peer-to-peer calls are also called “Point to Point” or “IP-to-IP” calls. You must know the 
peer’s IP address in order to do this.