ZyXEL Communications Intelligent Broadband Sharing Gateway P-324 - Manual (Page 172)

13-14 Filter Configuration
Figure 13-10 Example Filter — Menu 21.3.1
Press [ENTER] to confirm and display the next screen. Note that there is only one filter rule in this set.
Menu 21.7.1 - TCP/IP Filter Rule
Filter #: 7,1
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 #= 21
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= Check Next Rule
Press ENTER to Confirm or ESC to Cancel:
Press Space Bar to Toggle.
Press [SPACE BAR] 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 FTP is 21. See
RFC 1060 for port numbers of well-
known services. Select Equal here
as we are looking
for packets going
to port 21 only.
There are no
more rules to
check.
Select Drop so that the
packet will be dropped if its
destination is the telnet port.
Select Check Next Rule here so
that the next rule in this set will be
checked.