ZyXEL Communications NBG-318S - Manual (Page 133)

Chapter 12 Firewall
NBG-318S User’s Guide
133
1 A computer on the LAN initiates a connection by sending a SYN packet to a receiving
server on the WAN.
2 The NBG-318S reroutes the packet to Gateway A, which is in Subnet 2.
3 The reply from the WAN goes to the NBG-318S.
4 The NBG-318S then sends it to the computer on the LAN in Subnet 1.
Figure 70 Using IP Alias to Solve the Triangle Route Problem
12.3 General Firewall Screen
Click Security > Firewall to open the General screen. Use this screen to enable or disable the
NBG-318S’s firewall, and set up firewall logs.
Figure 71 Security > Firewall > General l
The following table describes the labels in this screen.
Table 49 Security > Firewall > General
LABEL DESCRIPTION
Enable Firewall Select this check box to activate the firewall. The NBG-318S performs access
control and protects against Denial of Service (DoS) attacks when the firewall is
activated.
Packet Direction This is the direction of travel of packets.
Firewall rules are grouped based on the direction of travel of packets to which they
apply.