Siemens Gigaset C450IP User Manual

Page 62

Web configurator

Gigaset C450 IP / Greek eng / A31008-M1713-T151-3-8U19 / web_server.fm / 24.9.07

Ver

on 4, 16.

09.20

Area:

Voice codecs

You can influence the quality of your VoIP

connections via the parameters in the

Voice codecs

area. In addition to the lan-

guage codecs used, you can activate/

deactivate "Silence Suppression" and

specify the language and earpiece volume

(

VoIP Volume

Your phone supports various voice codecs

for digitalising (coding and decoding)

voice data. The voice codec used on a

phone connection has a significant influ-

ence on the voice quality, e.g. through the

time need to code/decode (voice delay).

The choice of voice codec is a compromise

between voice quality and the necessary

bandwidth.
Both sides of a phone connection (caller/

sender side and receiver side) must be

using the same voice codec. The voice

codec is negotiated between the sender

and the recipient when establishing a con-

nection.
Set the voice codec that your phone sug-

gests when establishing a VoIP connec-

tion.
You can choose between the following

voice codecs supported by your phone:

G729

Average voice quality. The necessary

bandwidth is less than 8 Kbit/s per

voice connection.
To save additional bandwidth and

transmission capacity, on VoIP connec-

tions that use codec

G72

you can sup-

press the transmission of language

packages in pauses ("Silence Suppres-

sion",

Enable Annex B for G729

option).

Then, instead of the background noises

in your environment, your caller hears

a synthetic noise generated in the

receiver.
Please note: "Silence Suppression"

may mean a deterioration in the voice

quality.

G711 a law/G711 µ law

Excellent voice quality (comparable

with ISDN). The necessary bandwidth is

64 Kbit/s per voice connection.

G726

Good voice quality (inferior to that with

G.711 but better than with G.729).
Your phone supports G.726 with a

transmission rate of 32 Kbit/s per voice

connection.

In the

VoIP Volume

parameter, specify

the amplification level of the voice and

earpiece volume.
With some VoIP providers it may be the

case that the voice/earpiece volume is

too low or too high. Volume regulation

via the handset may then be insuffi-

cient.
You can pre-adjust the volume via the

VoIP Volume

parameter. You specify

whether the adjustable volume range

on the handset should be raised or low-

ered. The following choices are availa-

ble:

Low

Voice/earpiece volume is too low. If you

activate this option the volume is raised

by 6 dB.

Normal

The voice/earpiece volume does not

need to be raised/lowered.

High

Voice/earpiece volume is too high. If

you activate this option the volume is

lowered by 6 dB.

In the

Enable Annex B for G729

field, state

whether, when using codec

G729

transmission of data packages for

pauses is to be suppressed (

Yes