User Manual

Chapter 13 Firewall
NBG-418N v2 User’s Guide
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13.3 Wha t You Ne e d To Know
The NBG-418N v2’s firewall feature physically separates the LAN and the WAN and acts as a secure
gateway for all data passing between the networks.
13.3.1 About the NBG -418N v2 Fire wall
The NBG-418N v2 firewall is a stateful inspection firewall and is designed to protect against Denial of
Service attacks when activated (click the G e ne ral tab under Fire wall and then click the Ena ble Fire wa ll
check box). The NBG-418N v2's purpose is to allow a private Local Area Network (LAN) to be securely
connected to the Internet. The NBG-418N v2 can be used to prevent theft, destruction and modification
of data, as well as log events, which may be important to the security of your network.
The NBG-418N v2 is installed between the LAN and a broadband modem connecting to the Internet.
This allows it to act as a secure gateway for all data passing between the Internet and the LAN.
The NBG-418N v2 has one Ethernet WAN port and four Ethernet LAN ports, which are used to physically
separate the network into two areas.The WAN (Wide Area Network) port attaches to the broadband
(cable or DSL) modem to the Internet.
The LAN (Local Area Network) port attaches to a network of computers, which needs security from the
outside world. These computers will have access to Internet services such as e-mail, FTP and the World
Wide Web. However, "inbound access" is not allowed (by default) unless the remote host is authorized to
use a specific service.
13.3.2 VPN Pass Throug h Fe a ture s
A Virtual Private Network (VPN) is a way to securely connect two networks over the Internet. For
example a home network and one in a business office. This requires special equipment on both ends of
the connection.
The NBG-418N v2 is not one of the endpoints but it does allow traffic from those endpoints to pass
through. The NBG-418N v2 allows the following types of VPN traffic to pass through:
•IP security (IPSec)
• Point-to-Point Tunneling Protocol (PPTP)
13.4 Ge ne ra l Fire wall Sc re e n
Use this screen to enable or disable the NBG-418N v2’s firewall, and set up firewall logs. Click Se c urity >
Fire wall to open the Ge ne ra l screen.