Prestige 791R G.SHDSL Router

Menu 21.3.1 - TCP/IP Filter Rule

Filter #: 3,1

Filter Type= TCP/IP Filter Rule

Active= Yes

IP Source Route= No

IP Protocol= 6

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 #=

TCP Estab= No

Port # Comp= None

Log= None

More= No

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.

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 Equal here as we are looking for packets going to port 23 only.

The port number for the telnet service (TCP protocol) is 23. See RFC-1060 for port numbers of well- known services.

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 12-17 Sample Filter Rules Summary — Menu 21.3.1

After you have created the filter set, you must apply it.

Step 1. Enter 11 in the main menu to display menu 11 and type the remote node number to edit it. Step 2. Go to the Edit Filter Sets field, press [SPACE BAR] to choose Yes and press [ENTER].

Filter Configuration

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