The Security Tab - Filter; Figure 5-15: Security Tab - Firewall; Figure 5-16: Mac Filter Setting - Linksys EtherFast BEFSR41 User Manual

EtherFast Cable/DSL Router with 4-Port Switch

The Security Tab - Filter

When you click the Security tab, you will see the Filter screen. On this screen, set up filters to block specific
internal users from accessing the Internet and enhance your network's security.
Filter IP Address Range
You can create up to five different IP Address Range filters. To set up a filter using IP addresses, enter the range
of IP addresses you wish to filter in the Start and End fields. Users who have filtered IP addresses will not be able
to access the Internet at all. If you only want to filter one IP address instead of a range of IP addresses, enter the
same value into both fields. For instance, if you wish to filter the PC with the IP address of 192.168.1.5, enter 5
into both fields on one line: 192.168.1.5 ~ 192.168.1.5.
Filter Port Range
You can create up to five different Port Range filters. To filter users by network port number, select the protocol
you want to filter, TCP, UDP, or Both, from the Protocol drop-down menu. Enter the port numbers you want to
filter in the Start and End fields. Users connected to the Router will no longer be able to access any port number
listed there.
Filter MAC Address

Figure 5-15: Security Tab - Firewall

This feature blocks computers with specific MAC addresses from going out to the Internet. For information on
obtaining a MAC address, go to "Appendix C: Finding the MAC Address and IP Address for Your Ethernet Adapter."
To set the MAC filter, click the Edit MAC Filter Setting button.
Edit MAC Filter Setting. Click the Edit MAC Filter Setting button. Select the range of MAC address entries in the
drop-down box. In each mac field, enter the MAC address you want to filter. Click the Apply button before closing
the window. To cancel changes, click the Undo button.
Block WAN Requests
Use these features to enhance your network's security and filter multicasting.
Block Anonymous Internet Requests. This keeps your network from being "pinged" or detected and reinforces
your network security by hiding your network ports, so it is more difficult for intruders to work their way into your
network. Select Enabled to block anonymous Internet requests, or Disabled to allow anonymous Internet
requests.

Figure 5-16: MAC Filter Setting

Chapter 5: Configuring the Router 22
The Security Tab - Filter