Table 50 Port Forwarding Rule Setup (continued)
LABEL
Apply
Cancel
10.5.2 SIP ALG
Some NAT routers may include a SIP Application Layer Gateway (ALG). A SIP ALG allows
SIP calls to pass through NAT by examining and translating IP addresses embedded in the
data stream. When the ZyXEL Device registers with the SIP register server, the SIP ALG
translates the ZyXEL Device's private IP address inside the SIP data stream to a public IP
address. You do not need to use STUN or an outbound proxy if your ZyXEL Device is behind
a SIP ALG.
Use this screen to enable and disable the SIP (VoIP) ALG in the ZyXEL Device. To access
this screen, click Network > NAT > ALG.
Figure 83 Network > NAT > ALG
Each field is described in the following table.
Table 51 Network > NAT > ALG
LABEL
Enable SIP ALG
Apply
Reset
Chapter 10 Network Address Translation (NAT) Screens
Click Apply to save your changes back to the ZyXEL Device.
Click Cancel to begin configuring this screen afresh.
DESCRIPTION
Select this to make sure SIP (VoIP) works correctly with port-forwarding and
address-mapping rules.
Click this to save your changes and to apply them to the ZyXEL Device.
Click this to return to previously saved configuration.
P-2602H(W)(L)-DxA Series User's Guide
DESCRIPTION
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