ZyXEL Communications P-2802H-I Series, User Manual

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Chapter 10 Voice
P-2802H(W)(L)-I Series User’s Guide
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Figure 74 DiffServ: Differentiated Service Field
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.
10.3.3 VLAN Tagging
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.
10.4 SIP Settings Screen
The ZyXEL Device uses a SIP account to make outgoing VoIP calls and check if an incoming
call’s destination number matches your SIP account’s SIP number. In order to make or receive
a VoIP call, you need to enable and configure a SIP account, and map it to a phone port. The
SIP account contains information that allows your ZyXEL Device to connect to your VoIP
service provider.
If you want to make only peer-to-peer VoIP calls, there is no VoIP service provider involved,
so the SIP account information does not have to match a real VoIP service provider’s SIP
account. You can make up the SIP numbers. However, you should still activate a SIP account
and configure its number and map it to a phone port, so that the person you call knows what
SIP number you are using and the ZyXEL Device knows to which phone port it should
forward an incoming VoIP call. You must use speed dial to make peer-to-peer VoIP calls.
See
Section 10.8 on page 142 for how to map a SIP account to a phone port.
Use this screen to maintain basic information about each SIP account. You can also enable and
disable each SIP account. To access this screen, click
VoIP > SIP > SIP Settings .
DSCP
(6-bit) Unused
(2-bit)