ZyXEL Communications Corporation V630 Manuel D’Utilisation

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Chapter 14 SIP Account Setup
V630 User’s Guide
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• G.729 is an Analysis-by-Synthesis (AbS) hybrid waveform codec that uses a filter based 
on information about how the human vocal tract produces sounds. The codec analyzes the 
incoming voice signal and attempts to synthesize it using its list of voice elements. It tests 
the synthesized signal against the original and, if it is acceptable, transmits details of the 
voice elements it used to make the synthesis. Because the codec at the receiving end has 
the same list, it can exactly recreate the synthesized audio signal. G.729 provides good 
sound quality and reduces the required bandwidth to 8kbps.
14.2  SIP Settings Screen
Click SIP to open the following screen. Use this screen to maintain basic information about 
each SIP account. Your VoIP service provider (the company that lets you make phone calls 
over the Internet) should provide this.  
Figure 138   SIP