Prestige 652 ADSL Security Router

 

 

 

Press [SPACE BAR] to choose

Menu 21.1.9.1 - TCP/IP Filter Rule

 

Filter #: 9,1

 

 

this filter rule type. The first

 

 

filter rule type determines all

Filter Type= TCP/IP Filter Rule

 

Active= Yes

IP Source Route= No

 

subsequent filter types within a

IP Protocol= 6

 

set.

Destination: IP Addr= 0.0.0.0

 

IP Mask= 0.0.0.0

 

 

Port #= 23

 

 

Port # Comp= Equal

 

Select Yes to make the rule

Source: IP Addr= 0.0.0.0

 

IP Mask= 0.0.0.0

 

active.

Port #=

 

 

Port # Comp= None

 

 

TCP Estab= No

 

 

6 is the TCP protocol.

More= No

Log= None

 

Action Matched= Drop

 

 

 

Action Not Matched= Forward

 

 

 

 

Press ENTER to Confirm or ESC to Cancel:

 

 

 

 

 

 

 

The port number for the telnet

 

 

 

 

 

 

 

service (TCP protocol) is 23.

There are no

 

 

 

 

 

 

 

 

 

 

See RFC-1060 for port

Select Equal

 

 

more rules to

 

 

 

 

numbers of well-known

check.

 

 

here as we are

 

 

services.

 

 

 

 

looking for

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

packets going to

 

 

 

 

 

Select Drop here so that

 

 

 

 

 

 

 

port 23 only.

 

 

 

 

 

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.

 

 

 

 

 

 

 

 

Figure 16-15 Sample Filter — Menu 21.1.9.1

 

Step 5. Type 1 to configure the first filter rule. Make the entries in this menu as shown next.

When you press [ENTER] to confirm, the following screen appears. Note that there is only one filter rule in this set.

16-16

Filter Configuration