Administration Guide

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WP820 Administration Guide
Version 1.0.5.5
Voice Frames Per TX
Configures the number of voice frames transmitted per packet (It is recommended
that the IS limit value of Ethernet packet is 1500 bytes or 120Kbit/s). When
configuring this, it should be noted that the "ptime" value for the SDP will change
with different configurations here. This value is related to the codec used in the
codec table or negotiate the payload type during the actual call. For example, if
the setting is set to 2 and the first code is G. 729 or G. 711, the "ptime" value in
the SDP datagram of the INVITE request is 20 milliseconds. If the "Voice
Frame/TX" setting exceeds the maximum allowable value, the phone will use and
save the maximum allowable value for the selection of the first encoding. It is
recommended to use the default setting provided, and incorrect setting may affect
the voice quality.
Preferred Video Codec
Preferred Video
Codec
This parameter is to configure the preferred Video Codec used to receive and
display video for SIP calls on WP820. The default setting is H.264.
Enable Video FEC
When enabled, the video sender will temporarily allocate part of the bandwidth to
one data channel to send FEC data to system, thus to improve the video quality
the WP820 gets. Enabling this function will take up part of bandwidth and reduce
call rate. The default setting is "Yes"
Enable RFC5168
Support
Enables/disables RFC5168 mechanism for video calls to WP820. RFC5168 allows
SIP party to request the sender to refresh its video frame in H.264.The default
setting is “No”.
FEC Payload Type
Configures FEC payload type. The range is 96-126.
Default setting is 120.
H.264 Image Size
Sets the H.264 image size. It can be selected from the dropdown list.
• 720P
• 4CIF
• VGA
• CIF
• QVGA
• QCIF
Note: For some network environment, the default setting “720P” might be too high
that causes not receiving video or video quality issue during video call to WP820.
In this case, please change “H.264 Image Size” to “VGA” or “CIF” and change
“Video Bit Rate” to “384kbps” or lower. The default setting is 720P.