DHCP services between Windows NT 3.5 and Windows Server 2008 R2 hasn't really much changed, unless you're talking about R2’s new DHCP server service, that let you control which machines your DHCP server should give IP addresses to, and lets you do it in a fairly convenient way. Here’s an overview of R2’s DHCP MAC Filtering:

• Either block any particular MAC address from getting an IP address, or allow any particular MAC address to get an IP address.
• Arrange question of gets blocked from and who gets allowed to have an IP address either as a whitelist (no one gets an IP address unless their MAC address is on "allowed" list) or a blacklist (everyone gets an IP address unless their MAC address is on "deny" list).
• By default, DHCP runs as a blacklist with no IP addresses on "deny" list.
• R2's DHCP server lets you enter one or MAC addresses into its filters in several ways:
• hand-enter MAC address into GUI
• hand-enter a range of MAC addresses using "*" as a wild card
• select bunch of systems that already’ve a DHCP lease, right-click them and add them to either the allow or deny list with just a few mouse clicks
• feed DHCP server a text list of MAC addresses
• use a new command-line tool to enter one or more MAC addresses

Full Article: DHCP Server in R2

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