ZyXEL Communications P-2000W V2 - Manual (Page 7)

P2000W V2 Troubleshooting Guide
All contents copyright (c) 2005 ZyXEL Communications Corporation.
Voice quality is most commonly rated through a voice quality metric called the
Mean Opinion Score (MOS) which is recommendation by ITU-T. The MOS
is a 5 point scale where 5 represent excellent voice quality and 1 represent
bad voice quality.
11. What is codec?
Codec is an algorithm which converts analog signal into digital signal and vice
versa. There are three main types of waveform codec, source codec, and
hybrid codec. Each consume different amount of bandwidth and provide
different voice quality level.
12. What is the relation of codec and VoIP?
As VoIP is general term send voice information in digital form in discrete
packets over digital network and this digital network is public network, thus
there maybe other packet such data packet uses network at the same
time. The codec choose is related to how much bandwidth voice packet will
consume. In bandwidth wise aspect the smaller amount of bandwidth used
the better. But in voice aspect the higher quality the better.
13. Which codec should I choose?
As which codec choose is depending on what codec is supported on both end
of the VoIP host. Generally a codec with low bandwidth consumption and
high voice quality is a good codec.
14. I have press load default setting from Menu->Setting->Load
Default
option from the phone cursor but the device seems
not fully resetted?
'Load default' is not reset all of the settings. If you press the 'load default', it
will reset the Time format, Key lock, Melody, Ring volume, Banner and
Vibrator setting to default.
15. How do I reset the device to factory default?
To reset P2000W V2 to default including username/password. Please follow
the step as below.