What is a DHCP reservation (static DHCP mapping) and what advantage does it have over manually configuring a static IP on a device?

• A.A DHCP reservation is a backup DHCP scope that activates when the primary scope is exhausted
• B.A DHCP reservation encrypts the IP assignment using the device's MAC address as a key
• C.A DHCP reservation maps a specific MAC address to a fixed IP address on the DHCP server. The device always receives the same IP via DHCP. Advantage: all IP settings (gateway, DNS, subnet mask, DHCP options) are centrally managed on the DHCP server - no manual configuration on the device. Device moves to a new subnet → update reservation on the server, not on the device
• D.DHCP reservations replace static routes in the routing table for specific devices