ZyXEL Communications prestige 2602h series User Manual

Page of 550
Prestige 2602H/HW Series User’s Guide
Chapter 9 Voice Screens
145
9.6  Phone
You can configure the volume, echo cancellation and VAD settings for each individual phone 
port on the Prestige. You can also select which SIP account to use for making outgoing calls.
9.6.1  Voice Activity Detection/Silence Suppression
Voice Activity Detection (VAD) detects whether or not speech is present. This lets the 
Prestige reduce the bandwidth that a call uses by not transmitting “silent packets” when you 
are not speaking.
9.6.2  Comfort Noise Generation
When using VAD, the Prestige 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.
9.6.3  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.
9.7  Phone Configuration
Click Voice in the navigation panel and then Phone to display the following screen.