This should be basic, I want to create an additional subnet, but would like to leave the existing subnet unaltered. The existing subnet is 172.20.4.0/22. To make a new subnet, can I use the same bit mask with an address out of the existing range? For instance, would 172.20.8.0/22 be a valid subnet? Also, one I have the address range for the new subnet, how do I apply this? Do I need to apply an address from the subnet to an interface of a routing device, be it a core router or switch? If a DHCP server were involved, I would assume I would have to configure the scope of the new subnet. Any help or references on the topic would be appreciated.