The Dynamic Host Configuration Protocol provides configuration parameters to Intemet （）. DHCP consists of two components: a （） for delivering host-specific configuration parameters from a DHCP server to a host and a mechanism for allocation of network addresses to hosts. DHCP is built on a client-server model, where designated DHCP server hosts allocate network addresses and deliver （） parameters to dynamically configured hosts. DHCP supports three mechanisms for IP address allocation. In "automatic allocation", DHCP assigns a （） IP address to a client. In "dynamic allocation", DHCP assigns an IP address to a client for a limited period of time. In "manual allocation", a client's IP address is assigned by the network （）, and DHCP is used simply to convey the assitped address to the client.