DHCP snooping

Techniques

DHCP servers allocate IP addresses to clients on a LAN. DHCP snooping can be configured on LAN switches to exclude rogue DHCP servers and remove malicious or malformed DHCP traffic. In addition, information on hosts which have successfully completed a DHCP transaction is accrued in a database of bindings which may then be used by other security or accounting features.
Other features may use DHCP snooping database information to ensure IP integrity on a Layer 2 switched domain. This information enables a network to:

Track the physical location of IP addresses when combined with AAA accounting or SNMP.
Ensure that hosts only use the IP addresses assigned to them when combined with source-guard; a.k.a. source-lockdown
Sanitize ARP requests when combined with arp-inspection; a.k.a. arp-protect