[ Thanks to dave for
this link. ]
“Address Pool
This method entails defining a pool (sometimes also called a range
or scope) of IP addresses from which DHCP clients are supplied
their configuration properties dynamically and on a fist come first
serve basis. When a DHCP client is no longer on the network for a
specified period, the configuration is expired and released back to
the address pool for use by other DHCP Clients. MAC Address“This method entails using DHCP to identify the unique hardware
address of each network card connected to the network and then
continually supplying a constant configuration each time the DHCP
client makes a request to the DHCP server using that network
device.”