ZyXEL Communications 782R User Manual

Page of 166
Prestige 782R G.SHDSL Router
8-16 
Filter Configuration
Step 1.  Type 21 from the main menu to open Menu 21 – Filter Set Configuration.
Step 2.  Type the index of the filter set you want to configure (in this case 3) and press [ENTER]
.
Step 3.  Type a descriptive name or comment in the Edit Comments field (for eg. TELNET_WAN) and
press [ENTER].
Step 4.  Press [ENTER] at the message 
Press [ENTER] to confirm or [ESC] to cancel” to open Menu
21.3 – Filter Rules Summary.
Figure 8-12 Sample Filter – Menu 21.3.1
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 #=
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 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.
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 and
there are no more rules in this filter set to check.
Select Next if there are more rules to check.