DHCP Concepts and configuration steps

1 What is DHCP?

Dynamic Host Allocation Protocol (DHCP) is a standard protocol for TCP/IP that simplifies host IP address assignment management. Users can use DHCP servers to manage dynamic IP address assignments and other related environmental configuration tasks (such as DNS, WINS, gateway settings).

On a network that uses the TCP/IP protocol, each computer has a unique computer name and IP address. The IP address (and its subnet mask) uses and identifies the host and subnet to which it is connected, and must change the IP address of the computer when the user moves the computer from one subnet to another. If the use of static IP address allocation method will increase the burden of network administrators, and DHCP allows users to the DHCP server in the IP address database in the dynamic allocation of IP addresses to clients in the LAN, thereby reducing the burden of network administrators. Users can use the DHCP services provided by Windows 2000 servers to automatically assign IP addresses and related environments to the network.

When using DHCP, the entire network has a DHCP service installed on at least one NT Server, and other workstations that use DHCP must be set up to use DHCP to obtain IP addresses. As shown in Figure 1, a network instance that supports DHCP

1.2 Benefits of using DHCP:

Secure and reliable settings

DHCP avoids the error caused by manually setting IP addresses and subnet masks, and avoids the address conflicts that result from assigning an IP address to multiple workstations. Reduces the burden of managing IP address settings using a DHCP server greatly shortens the time spent in configuring or reconfiguring workstations on your network, while also flexibly setting the lease of an address by setting up a DHCP server. At the same time, the update of the DHCP address lease will help users to determine that the client's settings need to be updated frequently (for example, customers who use laptops often change locations), and that these changes are done automatically by the client and the DHCP server without network administrator intervention.

Common terms for 1.3 DHCP

Terminology description

Scope

A scope is a contiguous range of all the IP addresses that can be assigned to a network. Scopes are primarily used to define the IP address ranges of a single physical subnet in a network. Scopes are the primary means by which the server manages IP addresses assigned to network clients.

Super Scope

A superscope is a set of scopes that are used to implement a single physical subnet that contains multiple logical IP subnets. Contains only a list of member scopes or child scopes in a superscope. However, a superscope is not used to set specific scopes. The various properties of the child scope need to be set separately.

Exclusion Range

Exclusion ranges are sequences of IP addresses that are not used for assignment. It guarantees that the IP address in this sequence will not be assigned to the client by the DHCP server.

Address pool

After the user has defined the DHCP scope and exclusion range, the remaining address is a pool of addresses that can be dynamically assigned to clients in the network using

Lease

Leases are the length of time specified by the DHCP server, in which the client can use the IP address obtained. The lease is activated when the client obtains an IP address. The client needs to update the lease of the IP address before the lease expires, and the lease stops when the lease expires or is deleted from the server.