ZyXEL Communications P-334W User Manual

Page of 496
Prestige 334W User’s Guide 
30-14  
 
Filter Configuration 
 
Step 6.  Enter 1 to configure the first filter rule (the only filter rule of this set). Make the entries in this 
menu as shown in the following figure. 
Figure 30-10 Example Filter: Menu 21.1.3.1 
When you press [ENTER] to confirm, you will see the following screen. Note that there is only one filter rule 
in this set. 
                  Menu 21.1.3.1 - TCP/IP Filter Rule 
            Filter #: 3,1 
            Filter Type= TCP/IP Filter Rule 
            Active= Yes 
            IP Protocol= 6      IP Source Route= No 
            Destination: IP Addr= 0.0.0.0 
                         IP Mask= 0.0.0.0 
                         Port #= 23 
                         Port # Comp= Equal 
                 Source: IP Addr= 0.0.0.0 
                         IP Mask= 0.0.0.0 
                         Port #= 0 
                         Port # Comp= None 
            TCP Estab= No 
            More= No             Log= None 
            Action Matched= Drop 
            Action Not Matched= Forward 
 
            Press ENTER to Confirm or ESC to Cancel: 
Press Space Bar to Toggle. 
Press [SPACE BAR] and then 
[ENTER] to choose this filter rule 
type. The first filter rule type 
determines all subsequent filter 
types within a set. 
Select Yes to make the rule active. 
6 is the TCP protocol. 
The port number for the telnet 
service (TCP protocol) is 23. See 
RFC 1060 for port numbers of well-
known services. 
Select Equal here 
as you are looking 
for packets going 
to port 23 only. 
There are no 
more rules to 
check. 
Select Drop here so that the 
packet will be dropped if its 
destination is the telnet port. 
Select Forward here so that the 
packet will be forwarded if its 
destination is not the telnet port.