(第1空)The Dynamic Host Configuration Protocol provides configuration parameters to Internet ( ). 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 assigned address to the client.