DHCP Server :
A network application protocol used by equipments (DHCP clients) to obtain configuration information for operation in an IP (Internet Protocol) network is known DHCP (Dynamic Host Configuration Protocol).Making the definition simple, the configuration of DHCP enable sit to automatically provide the IP addresses to the network computers. It eliminates the need of assigning the IP address individually to the client systems. DHCP scope is the provided range of the numbers from which DHCP allocate IP address.
The protocol helps in decreasing the workload of administration and allows the addition of devices with less or no manual intervention. In October 1993, following the Bootstrap Protocol (BHOOTP) DHCP was defined as standard track protocol by the RFC 1531. Existing definition of DHCP for Internet Protocol version 4 (IPv4) networks was updated was updated in 1997 by the RFC 2131. RFC 3315, DHCP’s extensions for IPv6 were made available as RFC 3315.
Configuration of DHCP Servers:
Configuration of client computers enables them to access the IP addresses from the DHCP automatically during the boot up process. The configuration of DNS and WINS can be carried out along with DHCP server. From the defined pool of addresses, a computer on switching on gains the IP addresses by the help of DHCP. DORA ((Discover, Offer, Request, and Acknowledgement) is the process of assigning IP address by the DHCP server to the client computer. Following categories are of the allocation of IP address by the DHCP server:
The computer which has active DHCP client is turned on by the user.
The broadcast request, called DHCP Discover, is sent by the client computer that starts to look forward for the answer of DHCP.
On receiving the DHCP Discover packet, the DHCP server selects any IP address that is available, depending on the availability and defined settings, and then provides it to the client. With the available information of addresses, DHCP Offer is send back to the client by the DHCP server.
On using any of the address offered by the DHCP server, the client once again sends request to the DHCP server which is called DHCP Request.
DHCP server sends back an acknowledgment known as DHCP ACK to ensure that the certain IP address is assigned for a limited time period.
When two or more computers use same IP addresses and the IP address is static then there are chances of error. DHCP server is able to reduce any chances of such error. DHCP server enables the client computers to not only extract the IP addresses but also the settings (such as Firewall, Router, DNS, WINS, Gateway and Subnet masks) and configurations from the DHCP network on an IP network.
DHCP server assigns IP addresses for a limited time period and if the client computer needs the IP address for more time then it has to send a request of extension to the DHCP server before the expiration of initial IP address’ assigned time. In case, the extension request is not send within the time frame then the IP address is allocated to another client system on expiry. In case a client computer wants to change the assigned IP address then it has to send the command of “IPconfig/release then IPconfig/renew” to the DHCP server. After this command, existing IP address will be removed and new IP will be allocated.
Installing DHCP server on Windows 2000/2003
To install the DHCP server on Windows 2000 or Windows 2003 is very easy. Manage your service wizard can be used to install DHCP. On opening the wizard you have to select DHCP server option and you will be asked to enter the name and the description of the DHCP scope. It is able to reduce the load of work and to achieve multi-tasks by the help of DHCP server.