ZyAIR B-2000 Wireless LAN Gateway with 4-Port Switch

Step 3. Type a descriptive name or comment in the Edit Comments field (for example, TELNET_WAN) and press [ENTER].

Step 4. Press [ENTER] at the message “Press ENTER to confirm or ESC to cancel” to open Menu 21.3.1 – TCP/IP Filter Rule.

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

Menu 21.3.1 - TCP/IP Filter Rule

 

Filter #: 3,1

 

 

 

Select Yes to make the rule active.

 

 

 

 

 

 

 

Filter Type= TCP/IP Filter Rule

 

 

 

 

 

 

 

 

 

Active= Yes

 

 

 

 

 

 

IP Protocol= 6

IP Source Route= No

 

 

 

 

6 is the TCP protocol.

 

Destination: IP Addr= 0.0.0.0

 

 

 

IP Mask= 0.0.0.0

 

 

 

 

 

Port #= 23

 

 

 

 

 

Port # Comp= Equal

 

 

 

 

The port number for the telnet

 

Source: IP Addr= 0.0.0.0

 

 

 

IP Mask= 0.0.0.0

 

 

service (TCP protocol) is 23. See

 

Port #=

 

 

 

RFC-1060 for port numbers of well-

 

Port # Comp= None

 

 

known services.

 

TCP Estab= No

 

 

 

 

 

 

More= No

Log= None

 

 

 

 

 

 

 

 

 

Action Matched= Drop

 

 

 

 

 

Action Not Matched= Forward

 

 

Select Equal here

 

 

Press ENTER to Confirm or ESC to Cancel:

 

as we are looking

 

 

 

for packets going

 

 

 

 

 

 

to port 23 only.

 

There are no

 

 

 

 

 

 

 

 

 

 

 

more rules to

 

 

 

 

 

 

check.

 

 

Select Forward here so that the packet will be forwarded if

 

 

 

 

 

 

its destination is not the telnet port and there are no more

Select Drop here so that the

 

rules in this filter set to check. Select Next if there are

packet will be dropped if its

 

more rules to check.

 

 

 

destination is the telnet port.

Figure 7-12 Sample Filter – Menu 21.3.1

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

7-14

Filter Configuration