Avaya X330WAN Manual Do Utilizador

QoS and VoIP Treatment

Avaya X330WAN User’s Guide

57

VoIP Mode

The incoming packets are categorized into the Rx queues as in the Data mode.
The size of each of the four Tx queues is automatically set by X330WAN as follows:
•

 - Set by default to a maximum delay of 

20 milliseconds, optimized for a G.729 voice CODEC (without cRTP), and 
implements tail-drop when overflowed. This queue is divided into two 
priorities, 6 and 7, which are treated differently to improve distinction between 
the Voice Bearer (RTP) (priority 6) and Voice Control (priority 7) packets. The 
two priorities are serviced in a Round-Robin one-to-one fashion, where the 
priority 6 (RTP) buffer is 25% the size of the priority 7 (Voice Control) buffer to 
reduce the delay in VoIP flow. The priority 6-7 distinction exists in Data mode 
as well, where the queue is divided equally between both capacities.

•

The remaining queues are set using the same methods as in Data mode.

Figure 4.9 illustrates the queue and overflow concept for the Data and VoIP modes.

You can adjust the queue length in both modes for different needs. Queue 

length should always be kept as small as possible, while still maintaining a flow. It 
is recommended to always use the default queue length, as this is the optimal 
calculated length. To adjust the queue length in both modes, use the 

 

command.