DHCP
Dynamic Host Configuration Protocol (DHCP) is a communications protocol which allows network administrators to centrally automate, as well as manage the task of assigning IP addresses in a local network.
Through the help of an Internet Protocol (IP), each computer system that is connected to the
Internet must contain a unique IP address assigned to it while establishing a connection. In the absence of DHCP, the IP address must be configured manually for each computer system and each time the system connects to the Internet, a new IP address must be entered. DHCP enables a network administrator to monitor and allot IP addresses to a computer while it’s connected to a different place in the network.
The benefits of using DHCP are:
- Reliable configuration: Manual assignment of IP can cause typographical errors, thus, resulting in the accidental re-issuing of an already-assigned IP address to another system. However, DHCP helps get rid of this difficulty. It automates the entire system and minimizes configuration errors which may be a part of a manual configuration of IP.
- Reduced effort: Manually configuring IP addresses can be time-consuming and work intensive. On the other hand, DHCP does not require much time to configure.
- No duplication of IP addresses: Since DHCP brings the entire system under a central control, the duplication of IP address will never be a problem provided that the configuration is done correctly.
- Updating is easy: DHCP allows you to easily update a default IP address on the DNS servers. If manual changes are to be brought about in the system, the system administrator has to visit each computer system in the network which is quite a tedious job.
The permanent assignment of an IP address is recognized as DHCP reservation. DHCP reservation is a particular IP address within a network that is permanently reserved for a specific DHCP client. A DHCP reservation can be configured on a DHCP server, in case you need to reserve a permanent IP address.
The ipconfig/release option terminates any active TCP/IP connections on all network adapters and releases the IP addresses used by other applications. This option can be used with names of specific Windows connection. In cases like this, only the specified connection will be affected. You can either enter wildcard names or full connection names. For instance,
ipconfig/release “All Network Connection”
ipconfig/release ”Connection 1”
The following is the list of operating systems which include the DHCP Server service or are capable of handling a DHCP:
- Microsoft Windows® 98
- Microsoft Windows® Millennium Edition
- Microsoft Windows NT® Workstation°4.0
- Microsoft Windows® 2000 Professional
- Windows® XP Professional
- Windows Server® 2003
- Windows Vista®
- Windows Server® 2008
The enhancements are provided to the RFCs 2131 and 2132 by the DHCP in Windows server 2003 thus rendering it easier for a DHCP to deploy and manage the network. The enhancements provide the following:
- DHCP is integrated with the Domain Name System (DNS)
- Statistical reporting and monitoring is improved
- Address allocation is multi-casted
- Detection of unauthorized DHCP server
- Command-line management
The following enhancements are available in Windows Server 2008 with regard DHCP:
- The support of MAC address-based network allows the DHCP administrator to control the issuance/denial of IP addresses.
- DHCP prevents the name-squatting problems that are created as a result of non-Windows OS using the Name Protection Feature.
- It prevents the release of IP addresses at network level, especially in catering to high-availability/redundancy situations like Split-Scope.
- The DHCP administrators can monitor the configuration changes made on DHCP servers with the help of DHCP activity logging.
