Explanation
https://blogs.technet.microsoft.com/teamdhcp/2009/01/29/what-is-name-protection/Name Protection is based on the DHCID support to the DHCP server, and support for the new DHCID RR (Resource Record) to Microsoft DNS. In addition,support for DUID will be added to the IPv4 registration on the DHCP client.Therefore DHCID is a resource record stored in DNS like other RRs.This RR is intended to be used by DHCP to store an identifier for a machine, along with other information for the name such as a machine's A/AAAA records.DHCID effectively provides a mapping to determine if a name has already been assigned, and if the address of the machine assigned to the name is the same asthe machine requesting registration with this name.DHCP's unique position in the name registration process allows it to request this match, and then refuse the registration of a machine with a differentaddress attempting to register a name with an existing DHCID record.Prevents the following name squatting situations:- Server name squatting by a client- Server name squatting by another server- Client name squatting by another client- Client name squatting by a server