Trendnet VoIP Gateway User Manual

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TVP-221H User’s Guide 
Chapter 6 
Connection Considerations
 
This section discusses the special connection consideration for various environments and 
situations where you can use the VoIP Gateway. 
6.1 Port 
Configuration 
VoIP Gateway supports FXS and FXO ports. 
 
FXS (Foreign Exchange Station) 
FXS provides power and ringing signals to its interfacing equipment.  It is not 
intended for connection to the Public Switched Telephone Network.  It is a station 
loop start operation that provides a connection to:  
1.  A standard, single-line analog telephone system 
2.  The line circuit of a key telephone system 
3.  A loop start trunk circuit of a Private Branch Exchange (PBX) that normally 
connects to incoming Central Office circuits 
 
FXO (Foreign Exchange Office) 
FXO recognizes signals and draws current to indicate an active state.  It is a trunk 
loop start operation that emulates a single-line telephone to: 
1. Central Office lines 
2. PBX station 
 
There are two basic environments that the TVP-221H can be applied to.  They are 
described in the following sections. 
 
 
 
 
 
 
 
 
 
 
 
 
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