Prestige 645 ADSL Internet Access Router

Step 5. nter 1 to configure the first filter rule (the only filter rule of this set). Make the entries in this menu as shown in the following figure.

 

 

 

 

 

 

 

 

 

Press the [SPACE BAR] to

 

 

 

Menu 21.3.1 - TCP/IP Filter Rule

 

 

 

 

 

 

 

 

 

Filter #: 3,1

 

 

 

 

choose this filter rule type. The

 

 

 

 

 

 

 

first filter rule type determines

 

 

 

Filter Type= TCP/IP Filter Rule

 

 

 

 

 

Active= Yes

 

 

 

 

all subsequent filter types

 

 

 

 

 

 

 

 

 

 

 

 

IP Protocol= 6

IP Source Route= No

 

 

within a 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 #= 0

 

 

 

 

 

 

 

Port # Comp= None

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TCP Estab= No

 

 

 

 

 

 

 

 

 

More= No

Log= None

 

 

6 is the TCP protocol.

 

 

 

Action Matched= Drop

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Action Not Matched= Forward

 

 

 

 

 

 

 

Press ENTER to Confirm or ESC to Cancel:

 

 

 

 

 

 

 

 

 

 

 

 

Press Space Bar to Toggle.

 

 

 

 

The port number for the telnet

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There are no

 

 

 

 

 

 

service (TCP protocol) is 23.

 

 

 

 

Select Equal

 

See RFC 1060 for port

 

more rules to

 

 

 

 

 

check.

 

 

 

here as we are

 

numbers of well-known

 

 

 

 

 

 

looking for

 

services.

 

 

 

 

 

 

 

 

 

 

 

 

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.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 8-14 Example Filter – Menu 21.3.1

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

Filter Configuration

8-17