ZyXEL Communications MAX-206M1R User Manual

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User’s Guide
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 11  
The Phone Screens
11.1  Overview
Use the VOICE > Phone screens to configure the volume, echo cancellation, VAD 
settings and custom tones for the phone port on the WiMAX Modem. You can also 
select which SIP account to use for making outgoing calls.
11.1.1  What You Can Do in This Chapter
• The Analog Phone screen (
) lets you control which 
SIP accounts each phone uses.
• The Common screen (
) lets you activate and 
deactivate immediate dialing.
• The Region screen (
) lets you maintain settings that 
often depend on the region of the world in which the WiMAX Modem is located.
11.1.2  What You Need to Know
The following terms and concepts may help as you read through this chapter.
Voice Activity Detection/Silence Suppression/Comfort Noise
Voice Activity Detection (VAD) detects whether or not speech is present. This lets 
the WiMAX Modem reduce the bandwidth that a call uses by not transmitting 
“silent packets” when you are not speaking.
When using VAD, the WiMAX Modem generates comfort noise when the other 
party is not speaking. The comfort noise lets you know that the line is still 
connected as total silence could easily be mistaken for a lost connection.
Echo Cancellation 
G.168 is an ITU-T standard for eliminating the echo caused by the sound of your 
voice reverberating in the telephone receiver while you talk.