Polycom RMX 1500 Administrator's Manual page 461

11 View or modify the following fields:
Table 14-8 Default IP Service – Conferencing – QoS Parameters
Field
Enable
Type
Audio / Video
Polycom RMX 1500/2000/4000 Administrator's Guide
Description
Select to enable the configuration and use of the
QoS settings.
When un-checked, the values of the DSCP
(Differentiated Services Code Point) bits in the IP
packet headers are zero.
DiffServ and Precedence are two methods for
encoding packet priority. The priority set here for
audio and video packets should match the priority
set in the router.
•
DiffServ: Select when the network router uses
DiffServ for priority encoding.
The default priorities for both audio and video
packets is 0x88. These values are determined
by the QOS_IP_VIDEO and QOS_IP_AUDIO
flags in the system.cfg file. For more information
see "Modifying System Flags" on page 19-6.
•
Precedence: Select when the network router
uses Precedence for priority encoding, or when
you are not sure which method is used by the
router. Precedence should be combined with
None in the TOS field.
The default priority is 5 for audio and 4 for video
packets.
Note: Precedence is the default mode as it is
capable of providing priority services to all types
of routers, as well as being currently the most
common mechanism.
You can prioritize audio and video IP packets to
ensure that all participants in the conference hear
and see each other clearly. Select the desired
priority. The scale is from 0 to 5, where 0 is the
lowest priority and 5 is the highest. The
recommended priority is 4 for audio and 4 for video
to ensure that the delay for both packet types is the
same and that audio and video packets are
synchronized and to ensure lip sync.
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