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Web configurator – setting the phone using a PC
Gigaset S675/S685 IP / GBR / A31008-xxxx-xxxx-x-xxxx / web_server.fm / 5/18/09
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ion 8,
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8
STUN enabled
Click
No
to deactivate STUN.
Select
Yes
if you want your phone to use STUN.
¤
Select
Set
to save the changes.
Optimising voice quality for VoIP connections
You can make general and connection-specific settings to improve the voice
quality for VoIP telephony.
¤
Open the following Web page:
Settings
¢
Telephony
¢
Audio
.
The voice quality for VoIP connections is mainly determined by the
voice codec
used for transferring the data and the available
bandwidth
of your DSL con-
nection.
In the case of the voice codec, the voice data is digitalised (coded/decoded) and
compressed. A "better" codec (better voice quality) means more data needs to
be transferred, i.e. perfect voice data transfer requires a DSL connection with a
larger bandwidth.
The following voice codecs are supported by your phone:
G.722
Excellent voice quality. The
broadband
speech codec
G.722
works at the same
bit rate as G.711 (64 kbit/s per speech connection) but with a higher sampling
rate. This allows higher frequencies to be played back. The speech tone is there-
fore clearer and better than for the other codecs (High Definition Sound Per-
formance).
Gigaset S67H, S68H, SL37H and A58H handsets, for example, are HDSP-com-
patible.
G.711 a law / G.711 µ law
Excellent voice quality (comparable with ISDN). The necessary bandwidth is 64
kbit/s per voice connection.
G.726
Good voice quality (inferior to that with G.711 but better than with G.729).
Your phone supports G726 with a transmission rate of 32 kbit/s per voice con-
nection.
G.729
Average voice quality. The necessary bandwidth is less than or equal to 8 kbit/
s per voice connection.
Both parties involved in the telephone connection (caller/sender and receiver)
must use the same voice codec. The voice codec is negotiated between the
sender and the recipient when establishing a connection.
You can influence the voice quality by selecting (bearing in mind the band-
width of your DSL connection) the voice codecs your phone is to use, and spec-
ifying the order in which the codecs are to be suggested when a VoIP connec-
tion is established.