Adding an IP-to-MAC binding to the DHCP database
A routing switch maintains a DHCP binding database, which is used for DHCP and ARP packet validation. Both the DHCP snooping and DHCP Option 82 insertion features maintain the lease database by learning the IP-to-MAC bindings on untrusted ports. Each binding consists of the client MAC address, port number, VLAN identifier, leased IP address, and lease time.
If your network does not use DHCP or if some network devices have fixed, user-configured IP addresses, you can enter static IP-to-MAC address bindings in the DHCP binding database. The switch uses manually configured static bindings for DHCP snooping and dynamic ARP protection.