Cisco Cisco Aironet 340 Ethernet Bridges Guia Do Utilizador

Once you have added a filter for the IP protocol you may also filter 
packets based on their UDP or TCP port number, their IP sub-protocol 
(i.e., UDP/TCP/ICMP) or based on an IP address range.

To filter based on an IP sub- protocol use add ip_subprotocol. You are 
then prompted as to whether you want to filter tcp or udp or another pro-
tocol based on its ID number. Finally you are prompted for a filter 
action as in the other manual filters.

To filter based on port number use add ip_port. You are prompted as to 
whether you want to filter a TCP or UDP source or destination port. You 
are then prompted for the port number and the action associated with it.

To filter based on an IP address range use add ip_address. You are 
prompted as to whether you want to filter a source or destination address 
and then for an IP address and address mask and a filter action. The fil-
ter matches if the value of both the packet address and the filter address 
ANDED with the filter mask are equal.

Use the remove option to remove a protocol filter entry. You may either 
remove all filters by entering the keyword “all” or a single entry by 
entering the number assigned to the filter and shown at the start of the 
line in the filter display.

Use the length option to display the contents of packets being forwarded 
to the radio. 

Use this option to setup the filter mask values to properly narrow down 
which packets are filtered. 

If you add a protocol filter whose action is “log,” each time the filter 
matches, the contents of the data portion of the packet (after the MAC 
header) will be displayed on the console (in hexadecimal ) for a length in 
bytes determined by the value of this option.