Mask 2 then grants access to all address that begin with 192. Example 3: Allow access only by addresses that begin with 192, deny access to 192.1.1.5. Security Mask #1: 255.255.255.255 Mask #1 Action: Deny Security Mask #2: 192.255.255.255 Mask #2 Action: Permit Security Mask #3: ...