ZyXEL Communications P-2302R-P1 Series, User Manual

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P-2302R-P1 Series User’s Guide
Chapter 1 Introducing the ZyXEL Device 37
In this example, you use your analog phone (A in the figure) and the ZyXEL Device (B)
changes the call into VoIP and sends it to the IP-PBX. For PSTN phones (C), the IP-PBX
forwards calls through the PSTN network. For IP phones (D), the IP-PBX forwards calls
through an IP network (this could include the Internet).
Figure 3 IP-PBX Application
1.5.3 Make Peer-to-peer Calls
Use the ZyXEL Device 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.
The following figure shows a basic example of how you would make a peer-to-peer VoIP call.
You use your analog phone (A in the figure) and the ZyXEL Device (B) changes the call into
VoIP. The ZyXEL Device then sends your call through the Internet to the peer VoIP device
(C).
Figure 4 Peer-to-peer Calling