ZyXEL Communications ZyXEL Prestige 310 User Manual page 93

Step 3.
Enter a descriptive name or comment in the Edit Comments field (e.g., TELNET_WAN) and
press [Enter].
Step 4. Press [Enter] at the message: [Press ENTER to confirm] to open Menu 21.3.1 - Filter Rules
Summary.
Step 5. Enter 1 to configure the first filter rule. Make the entries in this menu as shown in the following
figure.
Filter #: 3,1
Filter Type= TCP/IP Filter Rule
Active= Yes
IP Protocol= 6
Destination: IP Addr= 0.0.0.0
TCP Estab= No
More= No
Action Matched= Drop
Action Not Matched= Forward
Press ENTER to Confirm or ESC to Cancel:
Press Space Bar to Toggle.
There are no
more rules to
check.
Select Drop here so that
the packet will be
dropped if its destination
is the telnet port.
Filters
Menu 21.3.1 - TCP/IP Filter Rule
IP Source Route= No
IP Mask= 0.0.0.0
Port #= 20
Port # Comp= Equal
Source: IP Addr= 0.0.0.0
IP Mask= 0.0.0.0
Port #= 0
Port # Comp= None
Log= None
Figure 7-11 Example Filter - Menu 21.3.1
Prestige 310 Broadband Sharing Gateway
Press [SPACEBAR] 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.
Select Next here so that the
next rule in this set will be
checked.
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