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Home: Configuring Filters
 

This section describes how to configure and manage MAC address, IP, and Ethertype filters on the access point using the web-browser interface.

Protocol filters (IP protocol, IP port, and Ethertype) prevent or allow the use of specific protocols through the access point’s Ethernet and radio ports. You can set up individual protocol filters or sets of filters. You can filter protocols for wireless client devices, users on the wired LAN, or both. For example, an SNMP filter on the access point’s radio port prevents wireless client devices from using SNMP with the access point but does not block SNMP access from the wired LAN.

IP address and MAC address filters allow or disallow the forwarding of unicast and multicast packets addressed to specific IP or MAC addresses. You can create a filter that passes traffic to all addresses except those you specify, or you can create a filter that blocks traffic to all addresses except those you specify.

You complete two steps to configure and enable a filter: 1) name and configure the filter using the filter setup pages and 2) enable the filter.

Configuring and Enabling MAC Address Filters
Configuring and Enabling IP Filters
Configuring and Enabling Ethertype Filters

Configuring and Enabling MAC Address Filters

MAC address filters allow or disallow the forwarding of unicast and multicast packets addressed to specific MAC addresses. You can create a filter that passes traffic to all MAC addresses except those you specify, or you can create a filter that blocks traffic to all MAC addresses except those you specify. You can apply the filters you create to either or both the Ethernet and radio ports and to either or both incoming and outgoing packets.

Follow these steps to create a MAC address filter.

  1. Click Services on the navigation menu to move to the Services Summary window.
  2. On the expanded Services menu, click Filters to move to the Services: Filters - Apply Filters page.
  3. On the Apply Filters page, click the MAC Address Filters tab at the top of the page.



  4. If you are creating a new MAC address filter, make sure <NEW> (the default) is selected in the Create/Edit Filter Index menu. To edit a filter, select the filter number from the Create/Edit Filter Index menu.
  5. In the Filter Index field, name the filter with a number from 700 to 799. The number you assign creates an access control list (ACL) for the filter.
  6. Enter a MAC address in the Add MAC Address field. Enter the address with periods separating the three groups of four characters (0040.9612.3456, for example).

    Note: If you plan to block traffic to all MAC addresses except those you specify as allowed, put your own MAC address in the list of allowed MAC addresses.
  7. Use the Mask entry field to indicate how many bits, from left to right, the filter checks against the MAC address. For example, to require an exact match with the MAC address (to check all bits) enter FFFF.FFFF.FFFF. To check only the first 4 bytes, enter FFFF.FFFF.0000.
  8. Select Forward or Block from the Action menu.
  9. Click Add. The MAC address appears in the Filters Classes field. To remove the MAC address from the Filters Classes list, select it and click Delete Class.
  10. Repeat Steps 6 through 9 to add addresses to the filter.
  11. Select Forward All or Block All from the Default Action menu. The default action of the filter must be the opposite of the action for at least one of the addresses in the filter. For example, if you enter several addresses and you select Block as the action for all of them, you must choose Forward All as the filter’s default action.
  12. Click Apply. The filter is saved on the access point, but it is not enabled until you apply it on the Apply Filters page.
  13. Click the Apply Filters tab to return to the Apply Filters page.



  14. Select the filter number from one of the MAC drop-down menus. You can apply the filter to either or both the Ethernet and radio ports, and to either or both incoming and outgoing packets.
  15. Click Apply. The filter is enabled on the selected ports.

Configuring and Enabling IP Filters

IP filters (IP address, IP protocol, and IP port) prevent or allow the use of specific protocols through the access point’s Ethernet and radio ports, and IP address filters allow or disallow the forwarding of unicast and multicast packets addressed to specific IP addresses. You can create a filter that passes traffic to all addresses except those you specify, or you can create a filter that blocks traffic to all addresses except those you specify. You can create filters that contain elements of one, two, or all three IP filtering methods. You can apply the filters you create to either or both the Ethernet and radio ports and to either or both incoming and outgoing packets.

Follow these steps to create IP filters for the access points.

  1. Click Services in the navigation menu to go to the Services Summary window.
  2. In the expanded Services navigation menu, click Filters to go to the Services: Filters - Apply Filters window.
  3. On the Apply Filters page, click the IP Filters tab at the top of the page.



  4. If you are creating a new filter, make sure <NEW> (the default) is selected in the Create/Edit Filter Index menu. To edit an existing filter, select the name from the Create/Edit Filter Index menu.
  5. Enter a descriptive name for the new filter in the Filter Name field.
  6. Select Forward all or Block all as the filter’s default action from the Default Action menu. The filter’s default action must be the opposite of the action for at least one of the addresses in the filter. For example, if you create a filter containing an IP addresses, an IP protocol, and an IP port and you select Block as the action for all of them, you must choose Forward All as the filter’s default action.
  7. To filter an IP address, enter an address in the Destination Address and Source Address fields.

    Note: If you plan to block traffic to all IP addresses except those you specify as allowed, put the address of your own PC in the list of allowed addresses to avoid losing connectivity to the access point.
  8. Type the mask for the destination and source addresses in the Mask field. Enter the mask with periods separating the three groups of four characters (1122.3344.5566, for example).
  9. Select Forward or Block from the Action menu.
  10. Click Add. The address appears in the Filters Classes field. To remove the address from the Filters Classes list, select it and click Delete Class. Repeat Step 7 through 10 to add addresses to the filter. If you do not need to add IP protocol or IP port elements to the filter, skip to Step 17 to save the filter on the access point.
  11. To filter an IP protocol, select one of the common protocols from the IP Protocol drop-down menu, or select the Custom radio button and enter the number of an existing protocol in the Custom field. Enter a protocol number from 0 to 255.
  12. Select Forward or Block from the Action menu.
  13. Click Add. The protocol appears in the Filters Classes field. To remove the protocol from the Filters Classes list, select it and click Delete Class. Repeat Step 11 to Step 13 to add protocols to the filter. If you do not need to add IP port elements to the filter, skip to Step 17 to save the filter on the access point.
  14. To filter a TCP or UDP port number, select one of the common port protocols from the TCP Port or UDP Port drop-down menus, or select the Custom radio button and enter the number of an existing port in one of the Custom fields. Enter a port number from 0 to 65535.
  15. Select Forward or Block from the Action menu.
  16. Click Add. The port appears in the Filters Classes field. To remove the port from the Filters Classes list, select it and click Delete Class. Repeat Step 14 to Step 16 to add ports to the filter.
  17. When the filter is complete, click Apply. The filter is saved on the access point, but it is not enabled until you apply it on the Apply Filters page.
  18. Click the Apply Filters tab to return to the Apply Filters page.



  19. Select the filter name from one of the IP drop-down menus. You can apply the filter to either or both the Ethernet and radio ports, and to either or both incoming and outgoing packets.
  20. Click Apply. The filter is enabled on the selected ports.

Configuring and Enabling Ethertype Filters

Ethertype filters prevent or allow the use of specific protocols through the access point’s Ethernet and radio ports. You can apply the filters you create to either or both the Ethernet and radio ports and to either or both incoming and outgoing packets.

Follow these steps to create Ethertype filters for the access point.

  1. Click Services in the navigation menu to go to the Services Summary window.
  2. In the expanded Services menu, click Filters to go to the Services: Filters - Apply Filters window.
  3. On the Apply Filters page, click the Ethertype Filters tab at the top of the page.



  4. If you are creating a new filter, make sure <NEW> (the default) is selected in the Create/Edit Filter Index menu. To edit an existing filter, select the filter number from the Create/Edit Filter Index menu.
  5. In the Filter Index field, name the filter with a number from 200 to 299. The number you assign creates an access control list (ACL) for the filter.
  6. Enter an Ethertype number in the Add Ethertype field.
  7. Enter the mask for the Ethertype in the Mask field.
  8. Select Forward or Block from the Action menu.
  9. Click Add. The Ethertype appears in the Filters Classes field. To remove the Ethertype from the Filters Classes list, select it and click Delete Class. Repeat Step 6 through Step 9 to add Ethertypes to the filter.
  10. Select Forward All or Block All from the Default Action menu. The filter’s default action must be the opposite of the action for at least one of the Ethertypes in the filter. For example, if you enter several Ethertypes and you select Block as the action for all of them, you must choose Forward All as the filter’s default action.
  11. Click Apply. The filter is saved on the access point, but it is not enabled until you apply it on the Apply Filters page.
  12. Click the Apply Filters tab to return to the Apply Filters page.



  13. Select the filter number from one of the Ethertype drop-down menus. You can apply the filter to either or both the Ethernet and radio ports, and to either or both incoming and outgoing packets.
  14. Click Apply. The filter is enabled on the selected ports.