4. End of transaction: DHCP ACK
Here the server acknowledges the client's request for an IP address. The basics of the packet are the same as for a DHCP OFFER. Once a client receives this packet, it keeps the IP address given until the expiry of the DHCP lease or until it sends a subsequent DHCP request.
UDP 220.127.116.11:67 (00:D0:BC:00:11:22) > 18.104.22.168:68 (00:00:39:1C:0C:32) DHCP ACK