P314 Broadband Sharing Gateway with 4-Port Switch
7-14
Filter Configuration
Figure 7-11
Example Filter
When you press
[ENTER]
to confirm, you will see the following screen. Note that there is only one filter rule
in this set.
Menu 21.3.1 - 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= Check Next Rule
Press ENTER to Confirm or ESC to Cancel:
Press Space Bar to Toggle.
Press the [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 the telnet
service (TCP protocol) is
23
.
See RFC 1060 for port numbers
of well-known services.
Select
Equal
here as we are
looking for
packets going to
port 23 only.
No more rules to
check to block
telnet.
Select
Drop
here so that
the packet will be
dropped if its destination
is the telnet port.
Select
Check Next Rule
here
so that the next rule is
checked if the destination is
not the telnet port.
