Which DHCP message is used by a client to inform a DHCP server that it accepts the assigned IP address?

The DHCP message used by a client to inform a DHCP server that it accepts the assigned IP address is the Request message. After a DHCP server offers an IP address to a client via the Offer message, the client must explicitly indicate acceptance of that offer by sending a Request message back to the server. This Request message not only confirms acceptance of the offered IP address but can also request the additional parameters offered by the DHCP server. Thus, the Request message plays a crucial role in the DHCP leasing process, ensuring that the server knows the client has accepted the address.

Other message types serve different purposes in the DHCP process. The Discover message is sent by the client to locate available DHCP servers; the Offer message is the server's response with an IP address for the client; and the Acknowledgement message is a confirmation sent by the server to finalize the lease after receiving the Request. Therefore, the Request message is essential in establishing a valid lease between the client and server.