806 and Multiple Static IP Address Filtering Configuration

[frank_lee]

Hi, hope someone could help give me some pointers, I am a beginner in this area.

I have a Cisco 806 router and my DSL provider (PacBell) has given me 5 static IP addresses for use.

I like to setup so that there is a firewall between these IP address (PCs) and the internet so I can allow only port 80,20,21,etc. to pass between PC 1 and PC 2 on the internet.

No firewall filtering is needed for PC 3,4 and 5.

Is it possible to setup this way with Cisco 806 router?

Thanks folks.

[David White]

This is possible using just extended access-lists. But to be more secure, you can also use the IOS Firewall Feature set to accomplish the same thing.

With just access-lists it would look something like this:

access-list 101 permit tcp any host pc1 eq 80

access-list 101 permit tcp any host pc1 eq 21

access-list 101 permit tcp any host pc1 eq 20

access-list 101 permit tcp any host pc2 eq 80

access-list 101 permit tcp any host pc2 eq 21

access-list 101 permit tcp any host pc2 eq 20

access-list 101 permit ip any host pc3

access-list 101 permit ip any host pc4

access-list 101 permit ip any host pc5

Now apply access-list 101 inbound on the outside interface of your router.

Sincerely,

David.