See explanation
Explanation/Reference:
Explanation:
We should create an access-list and apply it to the interface that is connected to the Server LAN because it can filter out traffic from both S2 and Core networks. To see which interface this is, use the "show ip int brief" command:

From this, we know that the servers are located on the fa0/1 interface, so we will place our numbered access list here in the outbound direction.
Corp1#configure terminal
Our access-list needs to allow host C - 192.168.125.3 to the Finance Web Server 172.22.109.17 via HTTP (port 80), so our first line is this:
Corp1(config)#access-list 100 permit tcp host 192.168.125.3 host 172.22.109.17 eq 80 Then, our next two instructions are these:
Other types of access from host C to the Finance Web Server should be blocked.

All access from hosts in the Core or local LAN to the Finance Web Server should be blocked.

This can be accomplished with one command (which we need to do as our ACL needs to be no more than
3 lines long), blocking all other access to the finance web server:
Corp1(config)#access-list 100 deny ip any host 172.22.109.17
Our last instruction is to allow all hosts in the Core and on the local LAN access to the Public Web Server (172.22.109.18) Corp1(config)#access-list 100 permit ip host 172.22.109.18 any Finally, apply this access-list to Fa0/1 interface (outbound direction) Corp1(config)#interface fa0/1 Corp1(config-if)#ip access-group 100 out Notice: We have to apply the access-list to Fa0/1 interface (not Fa0/0 interface) so that the access-list can filter traffic coming from both the LAN and the Core networks.
To verify, just click on host C to open its web browser. In the address box type http://172.22.109.17 to check if you are allowed to access Finance Web Server or not. If your configuration is correct then you can access it.
Click on other hosts (A, B and D) and check to make sure you can't access Finance Web Server from these hosts. Then, repeat to make sure they can reach the public server at 172.22.109.18. Finally, save the configuration Corp1(config-if)#end Corp1#copy running-config startup-config