H.323 Telephone Installation
Page 31
15-601046 Issue 17e (Wednesday, November 14, 2012)
IP Office
Installation: System H.323 Support
2.2.4 Adjusting DiffServ QoS
DiffServ is used to apply different 'quality of service' tags to the voice (RTP) and control signal (RTCP) elements of a VoIP
call. The IP Office system itself does not apply any different priority to data packets its receives or sends based on their
tags. However, when being used in a network where QoS is being used for prioritization by other devices, the IP Office's
settings should be set to match those expected for voice calls and their associated control signalling.
Enabling the DiffServ QoS Settings
1. Using IP Office Manager, retrieve the configuration from the system.
2. Select
System.
3. Select the LAN1 or LAN2 tab depending on which of the system's LAN interfaces you want to use to support
H.323 extensions.
4. Select the VoIP sub-tab.
5. Check the DiffServ Settings that are being used by the system. Note that the 2 rows are linked, the upper row
shows the DiffServ values in Hex numbers, the lower row shows the values in decimal. The hex values are equal to
the decimal multiplied by 4. Either row can be used to set the required values.
6. If these settings need to be changed, do so and then save the configuration back to the system.