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Examples of Log Messages

Following are examples of log messages. In all cases, the log entry shows the time stamp as

day, year-month-date

hour:minute:second.

Activation and Administration

[This entry indicates a power-up or reboot with initial time entry.]

[This entry shows an administrator logging in and out from IP address 192.168.0.2.]

[This entry shows a time-out of the administrator login.]

[This entry shows when the log was emailed.]

Dropped Packets

[These entries show an inbound FTP (port 21) packet, a User Datagram Protocol (UDP)

packet (port 6970), and an Internet Control Message Protocol (ICMP) packet (port 0) being

dropped as a result of the default inbound rule, which states that all inbound packets are

denied.]

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Keyword Blocking of HTTP Traffic

Use keyword blocking to prevent certain types of HTTP traffic from accessing your network.

The blocking can be always or according to a scheduled.

1.

Select

Security >

Block Sites

.

2.

Select one of the keyword blocking options:

•

Per Schedule

. Turn on keyword blocking according to the Schedule screen settings.

•

Always

. Turn on keyword blocking all the time, independent of the Schedule screen.

3.

In the Keyword field, enter a keyword or domain, click

Add Keyword,

and click

Apply

.

The Keyword list. supports up to 32 entries. Here are some sample entries:

•

Specify XXX to block http://www.badstuff.com/xxx.html.

•

Specify .com if you want to allow only sites with domain suffixes such as .edu or .gov.

•

Enter a period (

.

) to block all Internet browsing access.

Delete Keyword or Domain

1.

Select the keyword or domain that you want to delete from the list.

2.

Click

Delete Keyword

and click

Apply

to save your changes.

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Specify Trusted Computer

You can exempt one trusted computer from blocking and logging. The computer you exempt

has to have a fixed IP address.

1.

In the Trusted IP Address field, enter the IP address.

2.

Click

Apply

to save your changes.

Firewall Rules to Control Network Access

Your modem router has a firewall that blocks unauthorized access to your wireless network

and permits authorized inbound and outbound communications. Authorized communications

are established according to inbound and outbound rules. The firewall has the following two

default rules. You can create custom rules to further restrict the outbound communications or

more widely open the inbound communications:

•

Inbound

. Block all access from outside except responses to requests from the LAN side.

•

Outbound

. Allow all access from the LAN side to the outside.

Configure Firewall Rules

The Firewall Rules screen lets you configure custom rules to make exceptions to the default

rules. Exceptions can be based on the service or application, source or destination IP

addresses, and time of day. You can log traffic that matches or does not match the rule and

change the order of rule precedence. See

Set Up Services

on page

48 for information about

services.

All traffic attempting to pass through the firewall is subjected to the rules in the order shown in

the Rules table from the top (highest precedence) to the default rules at the bottom. In some

cases, the order of precedence is important to determine which communications are allowed

into or out of the network.

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To set up firewall rules:

1.

Select

Security >

Firewall Rules

to display the following screen:

2.

To add an inbound or outbound rule:

•

For an outbound rule, click

Add

under Outbound Services.

•

For an inbound rule, click

Add

under Inbound Services.

3.

To edit or delete a rule, select its button on the left side and click

Edit

or

Delete

.

4.

To change the order of precedence:

a.

Select its button on the left side of the table and click

Move

.

b.

At the prompt, enter the number of the new position and click

OK

.

5.

To open or close instant messaging, select one of the following radio buttons:

•

Close IM Ports

. Disables instant messaging traffic.

•

Open IM Ports

. Enables instant messaging traffic. IM ports are open by default.

6.

Click

Apply

to save your settings.

Inbound Rules (Port Forwarding)

Because the modem router uses Network Address Translation (NAT), your network presents

only one IP address to the Internet, and outside users cannot directly address any of your

local computers. However, by defining an inbound rule you can make a local server (for

example, a Web server or game server) visible and available to the Internet.

The rule tells the modem router to direct inbound traffic for a particular service to one local

server based on the destination port number. This is also known as port forwarding. Allowing

inbound services opens holes in your firewall. Enable only those ports that are necessary for

your network. The following are two examples of inbound rules.

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Note:

Some residential broadband ISP accounts do not let you run server

processes (such as a Web or FTP server) from your location. Your

ISP might periodically check for servers and suspend your account if

it discovers any active services at your location. If you are unsure,

refer to the acceptable use policy of your ISP.

Inbound Rule Example: A Local Public Web Server

If you host a public Web server on your local network, you can define a rule to allow inbound

Web (HTTP) requests from any outside IP address to the IP address of your Web server at

any time of day, as shown here and described following the figure:

The settings are:

•

Service

. From this list, select the application or service you want to allow or block. The

list already displays many common services, but you are not limited to these choices.

Use the Services screen to add any additional services or applications that do not already

appear. See

Set Up Services

on page

48.

•

Action

. Choose how you want to handle this type of traffic. You can block or allow

always, or you can block or allow according to the schedule you have defined in the

Schedule screen, described in

Schedule Services

on page

50.

•

Send to LAN Server

. Enter the IP address of the computer or server on your LAN that

receives the inbound traffic covered by this rule.

•

WAN Users

. These settings determine which packets are covered by the rule, based on

their source (WAN) IP address:

-

Any

. All IP addresses are covered by this rule.

-

Address range

. If this option is selected, you must fill in the Start and Finish fields.

-

Single address

. Enter the required address in the Start field.