The Best Walkthrough on What Is DHCP and Its Working

With the advancement of technology, the need to configure network settings manually has almost become nonexistent. Therefore, the configuration of network settings for our devices is the responsibility of multiple network protocols and models. In this tutorial on what is DHCP, you will learn about such a network concept, DHCP (Dynamic Host Configuration Protocol), which is responsible for connecting our system to the internet through the use of an IP address.

What is DHCP?


DHCP (Dynamic Host Configuration Protocol) is a network administration protocol that is responsible for the task of assigning an IP address to your system and network device. The DHCP network model is based on the client-server architecture, where the connection is established when the client device sends a request message to the server device for providing the system with an IP address.

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Mode of Allocation

The allocation method of assigning an address to the network system can be divided into two different ways:


1. Manual Allocation: This mode of allocation, as the name suggests, requires you to manually configure the network settings for your device rather than applying any network concept. This allocation mode is much more time-consuming and is prone to errors because of user intervention. Later in this tutorial on what is DHCP, you will learn more about the steps on connecting our system to the internet.

The manual allocation is done by accessing the network configuration settings of the device and also requires other related configurations such as subnet mask, default gateway, and preferred DNS server.

2. Dynamic Allocation: The dynamic allocation mode involves the client (user device) sending a request message to the server (DHCP host).

After which, the server shares all the required network resources to the client device and configures the device automatically so that the system can access the internet and various network services.

Working Of DHCP

Till this point, in the tutorial on what is DHCP, you will be clear with the concept that DHCP is responsible for automatically configuring the network settings for your devices by connecting to the DHCP server and receiving all the required network information.

Now go ahead, take a look at the steps that are involved during the DHCP connection:


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  • The first step is when the client broadcasts the DHCPDISCOVER message over the network channel to establish a network connection with the DHCP server.

This message indicates that the client device wants to connect to the internet through the DHCP server.


  • The second step is when the DHCP server receives the DHCPDISCOVER message. According to the message, the DHCP server reserves an IP address for the connecting client and other network configuration settings, including subnet-mask default gateway, preferred DNS server, and shares it with the client device through the DHCPOFFER message.


  • In the third step, the client responds to the DHCP server’s DHCPOFFER through a DHCPREQUEST message requesting the offered IP address and relevant network configuration sent by the DHCP server for the system.


  • In the last step, the server acknowledges the DHCPREQUEST broadcast from the client device and sends the DHCPACK packet to the DHCP client, which comprises the required network configuration for the client device.

Next, you will learn about some DHCP settings which are to an extent needed to control the IP address assignment, reservation requirement, and others.

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DHCP Settings


  • Scope: This attribute refers to the range of addresses available in the address pool of the DHCP server, and then it is assigned to the client device when the server receives the request message from the client system.
  • Lease: The Lease setting of the DHCP server is designed to prevent the hoarding of IP addresses by a single system. 

This is done by assigning an expiration time to the leased IP address so that the DHCP server has some minimum addresses left for other client devices in the network channel.

  • Address Reservation: In this DHCP setting, the client device requests the server to assign the same IP address to the device each time the address allocation takes place. This setting is done by identifying the client device by its MAC address when the IP address is assigned.


In this tutorial on what is DHCP, you learned about the two different ways of allocating network configuration for our device. Then, you also talked about the steps involved in establishing between the client and the DHCP server. Finally, you also saw some attributes related to the DHCP settings in this tutorial on ‘what is DHCP’.

If you want to learn about the topic in detail and its various protocols related to the DHCP, you can refer to Simplilearn’s Cyber Security Expert course. With the completion of your professional course, you will become proficient in network-related tasks, establishing network connections, controlling the flow of network data, and other network-specific skills.

Do you have any questions related to this tutorial on what is DHCP? If yes, feel free to mention them in the comment section at the bottom of this page. Our team will help you solve your queries ASAP.

About the Author

Anmol KapoorAnmol Kapoor

Anmol is a Research Analyst who aims to become a Data Scientist one day. He enjoys Data Management systems and analysis. You will find him reading a book when he is not working.

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