Wednesday, April 19, 2006
Access Lists. (Question #55)
Assume that the 192.168.15.16/28 network has a collection of Linux and Windows PCs on it. The addressing scheme is such that the Linux PCs have the addresses
192.168.15.17
192.168.15.19
192.168.15.21
and so on through to 192.168.15.29 while the Windows PCs have the addresses
192.168.15.18
192.168.15.20
192.168.15.22
and so on through to 192.168.15.30.
All the PCs connect to the core network via a router on the same subnet.
One day all the Windows PCs get infected by a virus and start sourcing large amounts of network traffic. Your task is to create an access list to be used on the router for the subnet which drops all network traffic from the Windows PCs while allowing traffic from the Linux PCs.
Can you create an ACL with just two access list entries that will match traffic sourced from all the Windows PCs and drop them while allowing all other traffic?
192.168.15.17
192.168.15.19
192.168.15.21
and so on through to 192.168.15.29 while the Windows PCs have the addresses
192.168.15.18
192.168.15.20
192.168.15.22
and so on through to 192.168.15.30.
All the PCs connect to the core network via a router on the same subnet.
One day all the Windows PCs get infected by a virus and start sourcing large amounts of network traffic. Your task is to create an access list to be used on the router for the subnet which drops all network traffic from the Windows PCs while allowing traffic from the Linux PCs.
Can you create an ACL with just two access list entries that will match traffic sourced from all the Windows PCs and drop them while allowing all other traffic?
