Introduction to DHCP

DHCP stands for Dynamic Host Configuration Protocol, which is used in the LAN/WAN computer networking to dynamically assign the IP addresses, Subnet mask, DHCP, FTP, DNS and default gateway address to the client computers.  DHCP provides any easy way to administer the large and complex networks.  Just imagine that how difficult and time consuming it is to manually assign the IP addresses and other parameters to the 1000 client computers.  DHCP is also recommended for the network servers such as DNS, DHCP, default gateway, web server, proxy server and print server whose addresses are rarely changed.  If the network servers need to be readdressed then changes the only applied through the DHCP and the client computers automatically get the new changes.

A client computer when boots up it automatically gets the configurations and other parameters from the DHCP server. Upon receiving the valid request from the client computers, the DHCP server assigns the IP addressees and other TCP/IP parameters from its predefined pool of addresses for a fixed duration of time.  DHCP provides the simplified network management and that’s why a new computer can be added to the existing network with the hassle of assigning the IP addressees and the other configurations.

Many ISPs, Ethernet networks and the corporate networks use the DHCP to assign the network configurations to the client computers. Depending upon the configurations, the DHCP assigns the addresses through the three following methods.

Dynamic Allocation

IP addresses are assigned from the fixed pool of the addresses.

Manual Allocation

IP addresses are assigned based on the MAC addresses of the system. The IP/MAC address pair is filled by the network administrators.

Automatic Allocation

The IP addressees are assigned permanently from the fixed pool that is defined by the network administrator.

After obtaining the IP addresses and other parameters from the DHCP server, the client do not require the manual configurations and they should be able to communicate with the other computers in the network. DHCP clients can co-exist with the statically configured computers in the network.  DHCP is installed by default in the Windows Server Computers such as Window 2000 Server, Windows 2000 Server, Windows 2003 Server and Windows 2008 Server etc.