ZyXEL Communications 240B manual Next diagram illustrates the logic flow of an IP filter

	ExpWave 240B Secure Outdoor Ethernet Radio Link
Field	Description	Option
	Matched will be N/A.
Log	Select the logging option from the following:
	None – No packets will be logged.	None
	Action Matched - Only packets that match the rule
		Action Matched
	parameters will be logged.
	Action Not Matched - Only packets that do not match the	Action Not Matched
	rule parameters will be logged.	Both
	Both – All packets will be logged.
Action Matched	Select the action for a matching packet.	Check Next Rule
		Forward
		Drop
Action Not Matched	Select the action for a packet not matching the rule.	Check Next Rule
		Forward
		Drop
Once you have completed filling in Menu 21.1.1 - TCP/IP Filter Rule, press [Enter] at the message [Press
Enter to Confirm] to save your configuration, or press [Esc] to cancel. This data will now be displayed on
Menu 21.1 - Filter Rules Summary.

The next diagram illustrates the logic flow of an IP filter.

Packet

into IP Filter

Filter Active?	No
Yes
Apply SrcAddrMask
to Src Addr
Check Src	Not Matched
IP Addr
Matched
Apply DestAddrMask
to Dest Addr
Check Dest	Not Matched
IP Addr
Matched
Check	Not Matched
IP Protocol
Matched
Check Src &	Not Matched
Dest Port
Matched
More?	Yes
No		Action Not Matched
Action Matched	Check Next Rule
	Check Next Rule	Drop	Forward
Drop	Forward
Drop Packet	Check Next Rule		Accept Packet

Filter Setup 9-5