Table 62 sip extension: advanced – ZyXEL Communications IP PBX X6004 User Manual
Page 234
Chapter 13 Authority Group
X6004 User’s Guide
234
Each field is described in the following table.
Table 62 SIP Extension: Advanced
LABEL
DESCRIPTION
Codec Setting
Select the type of voice coder/decoder (codec) that you want this
extension to use when communicating with the X6004. The following
codecs (shown in highest quality to lowest quality order) are supported
by the X6004:
• G.711 a-law (typically used in Europe)
• G.711 u-law (typically used in North America and Japan)
• G.729A
• G.722 (pass-through)
• G.722 AMR-WB (pass-through)
• G.723.1 - you must activate support for this codec in the
Configuration > PBX > Server Configuration > Server screen.
• G.726
for more information.
When two SIP devices start a SIP session, they must agree on a codec.
If these SIP extensions are assigned to videophones, you must specify
the video codecs used for video calls. The X6004 allows the following
video codecs to passthrough:
• H.261
• H.263
• H.264
• MP4
for more information.
Codec Pool
This column indicates the codec types not used by this extension. You
can add a codec type to be used by this extension by highlighting it and
hitting the Right button.
Codec List
This column indicates the codec types used by this extension. You can
organize the priority of the codecs by highlighting it and clicking the Up
or Down buttons to move the codec higher or lower in priority. The SIP
extension attempts to use the higher priority codecs first and tries the
lower priority codecs next. You can remove a codec type from being
used from this extension by highlighting it and hitting the Left button.
Extra Setting
DTMF Mode
Control how the X6004 handles the tones that the IP phone using this
extension makes when you push its buttons. One use of the tones is to
distinguish between numbers when trying to dial a PSTN phone
number. You should use the same mode as your VoIP service provider.
The choices are:
• rfc2833 - Follow the RFC 2833 standard and send the DTMF tones
in RTP packets.
• inband - Send the DTMF tones in the voice data stream. This works
best when you are using a codec that does not use compression (like
G.711). Codecs that use compression (like G.729) can distort the
tones.
• info - Send the DTMF tones in SIP messages.