Security

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N300 Wireless Gigabit Router WNR3500Lv2

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 schedule.

1.

Select

Advanced > Security >

Block Sites

to display the following screen:

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.



To delete a keyword or domain:

1.

Select the keyword you want to delete from the list.

2.

Click

Delete Keyword,

and then

Apply

to save your changes.



To specify a 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.

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N300 Wireless Gigabit Router WNR3500Lv2

Block Services (Port Filtering)

Services are functions performed by server computers at the request of client computers. For

example, web servers serve web pages, time servers serve time and date information, and

game hosts serve data about other players’ moves. When a computer on the Internet sends

a request for service to a server computer, the requested service is identified by a service or

port number. This number appears as the destination port number in the transmitted IP

packets. For example, a packet that is sent with the destination port number 80 is an HTTP

(web server) request.

The service numbers for many common protocols are defined by the Internet Engineering

Task Force (IETF at

) and published in RFC1700, “Assigned Numbers.”

Service numbers for other applications are typically chosen from the range 1024 to 65535 by

the authors of the application. Although the router already holds a list of many service port

numbers, you are not limited to these choices. You can often determine port number

information by contacting the publisher of the application, by asking user groups or

newsgroups, or by searching.

The Block Services screen lets you add and block specific Internet services by computers on

your network. This is called service blocking or port filtering. To add a service for blocking,

first determine which port number or range of numbers are used by the application.



To block services:

1.

Select

Advanced > Security > Block Services

to display the following screen:

2.

Select either

Per Schedule

or

Always

to enable service blocking, and click

Apply

. If you

selected Per Schedule, specify a time period in the Schedule screen as described in

Schedule Blocking

on page 58.

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N300 Wireless Gigabit Router WNR3500Lv2

3.

Click

Add

to add a service. The Block Services Setup screen displays:

4.

From the Service Type list, select the application or service to allow or block. The list already

displays several common services, but you are not limited to these choices. To add any

additional services or applications that do not already appear, select

User Defined.

5.

If you know that the application uses either TCP or UDP, select the appropriate protocol. If

you are not sure, select

Both

.

6.

Enter the starting and ending port numbers. If the application uses a single port number,

enter that number in both fields.

7.

Select the radio button for the IP address configuration you want to block, and enter the IP

addresses. You can block the specified service for a single computer, a range of computers

with consecutive IP addresses, or all computers on your network.

8.

Click

Add

to enable your Block Services Setup selections.

Schedule Blocking

You can specify the days and time that you want to block Internet access.



To schedule blocking:

1.

Select

Advanced > Security > Schedu le

to display the following screen:

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N300 Wireless Gigabit Router WNR3500Lv2

2.

Set up the schedule for blocking keywords and services.

•

Days to Block

. Select days on which you want to apply blocking by selecting the

appropriate check boxes, or select

Every Day

to select the check boxes for all days.

•

Time of Day to Block

. Select a start and end time in 24-hour format, or select

All

Day

for 24-hour blocking.

3.

Select your time zone from the list. If you use daylight savings time, select the

Automatically adjust for daylight savings time

check box.

4.

Click

Apply

to save your settings.

Security Event Email Notifications

To receive logs and alerts by email, provide your email information in the Email screen, and

specify which alerts you want to receive and how often.



To set up email notifications:

1.

Select

Advanced > Security >

Email

to display the following screen:

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N300 Wireless Gigabit Router WNR3500Lv2

2.

To receive email logs and alerts from the router, select the

Turn Email Notification On

check box.

3.

In the Your Outgoing Mail Server field, enter the name of your ISP’s outgoing (SMTP) mail

server (such as mail.myISP.com). You might be able to find this information in the

configuration screen of your email program. If you leave this field blank, log and alert

messages are not sent by email.

4.

Enter the email address to which logs and alerts are sent in the Send to This Email Address

field. This email address is also used for the From address. If you leave this field blank, log

and alert messages are not sent by email.

5.

If your outgoing email server requires authentication, select the

My Mail Server requires

authentication

check box. Fill in the User Name and Password fields for the outgoing email

server.

6.

You can have email alerts sent immediately when someone attempts to visit a blocked site

and you can specify that logs are sent automatically.

If you select the Weekly, Daily, or Hourly option and the log fills up before the specified

period, the log is automatically emailed to the specified email address. After the log is

sent, the log is cleared from the router’s memory. If the router cannot email the log file, the

log buffer might fill up. In this case, the router overwrites the log and discards its contents.

7.

Click

Apply

to save your settings.