ZyXEL Communications P-2602 Manuel D’Utilisation

P-2602H(W)(L)-DxA Series User’s Guide

Chapter 11 Voice

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The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each 
packet gets across the DiffServ network.  Based on the marking rule, different kinds of traffic 
can be marked for different priorities of forwarding. Resources can then be allocated 
according to the DSCP values and the configured policies.

Virtual Local Area Network (VLAN) allows a physical network to be partitioned into multiple 
logical networks. Only stations within the same group can communicate with each other. 

Your ZyXEL Device can add IEEE 802.1Q VLAN ID tags to voice frames that it sends to the 
network. This allows the ZyXEL Device to communicate with a SIP server that is a member of 
the same VLAN group. Some ISPs use the VLAN tag to identify voice traffic and give it 
priority over other traffic.

Use this screen to maintain ToS and VLAN settings for the ZyXEL Device. To access this 
screen, click VoIP > SIP > QoS.

Figure 90   SIP > QoS

Each field is described in the following table.

Table 56   SIP > QoS

SIP TOS Priority 

Setting

Enter the priority for SIP voice transmissions. The ZyXEL Device creates Type of 

Service priority tags with this priority to voice traffic that it transmits.

RTP TOS Priority 

Setting

Enter the priority for RTP voice transmissions. The ZyXEL Device creates Type of 

Service priority tags with this priority to RTP traffic that it transmits.

Voice VLAN ID

Select this if the ZyXEL Device has to be a member of a VLAN to communicate 

with the SIP server. Ask your network administrator, if you are not sure. Enter the 

VLAN ID provided by your network administrator in the field on the right. Your LAN 

and gateway must be configured to use VLAN tags.
Otherwise, clear this field.