Which method does a DHCP client use to locate a DHCP server?

A DHCP client locates a DHCP server primarily using a broadcast method. When a device first connects to a network and needs an IP address, it does not know the address of any DHCP server on that network. To initiate this process, the DHCP client sends a DHCP Discover message as a broadcast to the entire local subnet. This broadcast is addressed to the MAC address of "all hosts" (FF:FF:FF:FF:FF:FF), allowing all devices on the local networksegment to receive the message.

Once this broadcast is sent, any DHCP servers that are listening will respond with a DHCP Offer message, also sent as a broadcast. This broadcast-based approach is essential because it ensures that the client can reach out to any available DHCP server without prior knowledge of its location.

In contrast, unicast transmission would require the client to know a specific address to send the request, which it does not have at the beginning of the process. Multicast transmission is used for messages sent to a group of interested receivers but is not applicable in the initial DHCP discovery phase. Direct inquiry implies sending a request to a known address, which again is not feasible for a client that is just connecting to the network.