Dynamic Host Configuration Protocol

The Dynamic Host Configuration Protocol (DHCP) helps make sure that any new machines that join a network can negotiate with existing machines to receive a properly configured and unique IP address. Unlike ICMP, it takes an active role in preventing issues rather than simply reporting on them.

DHCP achieves its goal via centralization. A DHCP server is used to assign an IP address to each host that joins its network. We can think of the DHCP server as handing a sort of ticket to each machine. Each ticket contains a unique number, and only remains valid for a predetermined amount of time.

DHCP behaves similarly. Every IP address that joins the network receives a unique IP address, and is only allowed to keep it for some defined time frame before it must check in with the DHCP server to revalidate.

The DHCP server also provides the joining host with several other pieces of information, like the network's subnet mask, its default gateway address, and its Domain Name Server (DNS) address(es).

Relevant Note(s): Network Protocols