How Does a DHCP Server Work?
When a computer is connected to a network that uses the DHCP protocol, it sends a request called a DISCOVER or DHCPDISCOVER message in an attempt to find a DHCP server on the network. The network router will then send the DISCOVER packet to the best or closest DHCP server to answer the request. The server will then determine an appropriate IP address for the computer based on the administrator-set policies and address availability on the network. Once this assignment is made, it sends an “OFFER” or “DHCPOFFER” packet back to the client computer with the network address information. Once the client computer receives this response, it sends a “DHCPREQUEST” or “REQUEST” packet back to the server to let it know that the address will be used. The DHCP server will then send an “ACK” or “DHCPACK” packet back to confirm the IP address lease and time of the lease.
