Set Up A Dmz To Lan Firewall Rule For Sip - ZyXEL Communications USG-100@USG-200 - V2.20 ED 2 Manual

Click Configuration > Firewall > Add. Set the From field as WAN and the To
1
field as DMZ. Set the Destination to the IPPBX's DMZ IP address object
(DMZ_SIP). IPPBX_DMZ is the destination because the ZyWALL applies NAT to
traffic before applying the firewall rule. Set the Access field to allow and click
OK.
Figure 141 Configuration > Firewall > Add

7.13.5 Set Up a DMZ to LAN Firewall Rule for SIP

The firewall blocks traffic from the DMZ zone to the LAN zone by default so you
need to create a firewall rule to allow the IPPBX to send SIP traffic to the SIP
clients on the LAN.
ZyWALL USG 100/200 Series User's Guide
Chapter 7 Tutorials
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