ZyXEL Communications max208m User Manual

 Chapter 9 The VoIP General Screens

WiMAX Device Configuration User’s Guide

Click VoIP > General > Media to set up and maintain global VoIP settings.

Media

The following table describes the labels in this screen.

Media

Port Range

Media Port Start

Media Port End

Enter the listening port number(s) for RTP traffic on the WiMAX Device, if your 
VoIP service provider gave you this information. Otherwise, keep the default 
values.

To enter one port number, enter the port number in the both Media Port Start 
and Media Port End fields.

To enter a range of ports, enter the beginning port number of the range in the 
Media Port Start field and the ending port number in the Media Port End field.

Codec Packetization Time Settings

G.711, G.729

Select how often (10 to 60 msecs) the WiMAX Device sends an RTP packet for 
each type of voice coder/decoder (codec) G.711 and G.729. 

Advanced

Voice Jitter Buffer 
Type

Voice jitter is a variation in delay of RTP packets delivery. This could cause 
strange sound effects. The WiMAX Device can utilize the following types of jitter 
buffer to minimize the effects of jitter.

Dynamic - Jitter buffer size is dynamically changed by RTP packets delivery 
status.

Static - Jitter buffer size is fixed.

Voice Jitter Buffer 
Length

Select the maximum number of milliseconds of voice traffic the WiMAX Device 
can help to smooth out the jitter in order to ensure good voice quality for your 
conversations.