ZyXEL Communications Internet Security Gateway ZyWALL 100 - Manual (Page 173)

ZyWALL 100 Internet Security Gateway
Creating Custom Rules 16-3
16.2.3 Key Fields For Configuring Rules
Action
Should the action be to Block or Forward?
“Block” means the firewall silently discards the packet.
Service
Select the service from the Service scrolling list box. If the service is not listed, it is necessary to first define
it. See section 16.5 for more information on predefined services.
Source Address
What is the connection’s source address; is it on the LAN, DMZ or WAN? Is it a single IP, a range of IPs or
a subnet?
Destination Address
What is the connection’s destination address; is it on the LAN, DMZ or WAN? Is it a single IP, a range of
IPs or a subnet?
16.3 Connection Direction Examples
This section describes examples for firewall rules for connections going from LAN to WAN and from WAN
to LAN. Rules for the DMZ work in a similar fashion.
You can configure LAN to LAN/DMZ (or DMZ to DMZ/ZyWALL) rules to subdivide a LAN (or DMZ)
based on subnets (computers on one subnet are blocked from accessing those on another subnet). You can
configure WAN to WAN/ZyWALL rules to allow administrators to remotely manage the ZyWALL from the
WAN.
16.3.1 LAN to WAN Rules
The default rule for LAN to WAN traffic is that all users on the LAN are allowed non-restricted access to the
WAN. When you configure Policy -> LAN to WAN -> Rules, you in essence want to limit some or all users
from accessing certain services on the WAN. See the following figure.