User's Manual

Control Access to the Internet
25
U.S. Cellular® 4G LTE Router (LG2200D)
4. In the Keyword field, enter a keyword or domain that you want to block.
For example:
• 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.
5. Click the Add Keyword button.
The keyword is added to the keyword list. The keyword list supports up to 32 entries.
6. Click the Apply button.
Keyword blocking takes effect.
¾ To delete keywords from the list:
1. Do one of the following:
• To delete a single word, select it and click the Delete Keyword button.
The keyword is removed from the list.
• To delete all keywords on the list, click the Clear List button.
All keywords are removed from the list.
2. Click the Apply button.
Your changes are saved.
Block Services from the Internet
Services are functions that server computers perform 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 players’ moves. When a computer on the Internet sends a
request for service to a server computer, a port number identifies the requested service. This
number displays 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 Internet Engineering Task Force (IETF at http://www.ietf.org/) defines service numbers
for many common protocols and they are published in RFC1700, “Assigned Numbers.”
Authors of the applications typically choose service numbers from the range 1024–65535.
Although the router already holds a list of many service port numbers, you are not limited to
these choices. You can often find 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 find out which port number or range of numbers the application uses.