Chapter 13 Firewall

The following table describes the labels in this screen.

Table 50 Security > Firewall > General

LABEL

DESCRIPTION

Enable Firewall

Select this check box to activate the firewall. The NBG-417N performs access

 

control and protects against Denial of Service (DoS) attacks when the firewall is

 

activated.

 

 

Apply

Click Apply to save the settings.

 

 

Reset

Click Reset to start configuring this screen again.

 

 

13.5 Services Screen

If an outside user attempts to probe an unsupported port on your NBG-417N, an ICMP response packet is automatically returned. This allows the outside user to know the NBG-417N exists. Use this screen to prevent the ICMP response packet from being sent. This keeps outsiders from discovering your NBG-417N when unsupported ports are probed.

You can also use this screen to enable service blocking, enter/delete/modify the services you want to block and the date/time you want to block them.

Click Security > Firewall > Services. The screen appears as shown next.

Figure 77 Security > Firewall > Services

The following table describes the labels in this screen.

Table 51 Security > Firewall > Services

LABEL

DESCRIPTION

ICMP

Internet Control Message Protocol is a message control and error-reporting

 

protocol between a host server and a gateway to the Internet. ICMP uses

 

Internet Protocol (IP) datagrams, but the messages are processed by the TCP/IP

 

software and directly apparent to the application user.

 

 

Respond to Ping

The NBG-417N will not respond to any incoming Ping requests when Disable is

on

selected. Select LAN to reply to incoming LAN Ping requests. Select WAN to

 

reply to incoming WAN Ping requests. Otherwise select LAN & WAN to reply to

 

all incoming LAN and WAN Ping requests.

 

 

 

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NBG-417N User’s Guide