Advantages of DHCP
DHCP has a number of advantages:
- There is no need to manually configure each client with an IP address.
- You don't need to keep a record of the IP addresses that you have assigned.
- You can automatically assign a new IP address if you move a client to a different subnet.
- You can release the IP address of a computer that is offline and reassign the address to another computer.
- Address duplication is eliminated as DHCP automatically tracks IP address assignments.
- The DHCP server can detect unauthorised DHCP servers on the network.
When a DHCP server receives a request from a client, it chooses an IP address and other related information from a pool of addresses known as a scope and offers it to the client. Certain addresses within the scope may be excluded from distribution because they have already been assigned as static addresses.
If the client accepts the address offered, the IP addressing information is leased to it for a specified duration. During this time, the client renews the address assignment each time it logs on to the network. If the lease period expires without a renewal, the IP address is returned to the pool for reassignment.
The DHCP server provides the client with the following configuration information:
- IP address
- Subnet mask
- Default gateway
Other configuration information, such as DNS server addresses and Windows Internet Name Service (WINS) server addresses can also be distributed by DHCP.
Clients must be enabled to use DHCP by clicking Obtain an IP address automatically in the Internet Protocol (TCP/IP) Properties dialog box. This is selected by default in Windows Server 2003.
Next: The Ipconfig Utility