The Dynamic Host Configuration Protocol (DHCP) is an automatic configuration protocol used on IP networks. Computers that are connected to non-DHCP equipped IP networks must be configured before they can communicate with other computers on the network. DHCP allows a computer to be configured automatically, eliminating the need for intervention by a network administrator. It also provides a central database for keeping track of computers that have been connected to the network. This prevents two computers from accidentally being configured with the same IP address.
In the absence of DHCP, hosts may be manually configured with an IP address. Alternatively IPv6 hosts may use stateless address autoconfiguration to generate an IP address. IPv4 hosts may use link-local addressing to achieve limited local connectivity.
In addition to IP addresses, DHCP also provides other configuration information, particularly the IP addresses of local caching DNS resolvers. Hosts that do not use DHCP for address configuration may still use it to obtain other configuration information.
There are two versions of DHCP, one for IPv4 and one for IPv6. While both versions bear the same name and perform much the same purpose, the details of the protocol for IPv4 and IPv6 are sufficiently different that they can be considered separate protocols.