DHCP: All You Need To Know About DHCP

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What is DHCP? All You Need To Know About DHCP

How Does Dynamic Host Configuration Protocol:(DHCP) work?

What Is DHCP

 

Dynamic Host Configuration Protocol (DHCP) is designed to offer automatic, quick, and central management for distributing IP addresses in a network.

You can also use it configure a default gateway, subnet mask, and DNS server data on the device.

How does DHCP work?

This server is normally used to provide unique IP addresses while automatically configuring the other information of the network. A router can also work as the DHCP server in a home and small businesses. Even a single computer can work as DHCP server in large networks.

The process will be simple. A client (device) can request an IP address using a router and then the router will assign an available IP address to enable the device to communicate on that network.

Once the device is connected to the network with a DHCP server, it needs to send a request to the server, known as DHCPDISCOVER request.

Once the DHCP server receives that request, it will keep that IP address for the usage of that device and then it will provide an address with the DHCPOFFER packet.

After the offer is made for that particular chosen IP address, the client (device) will have to respond with a DHCPREQUEST packet to the DHCP server for the approval. Once it is done, the server will send an ACK to confirm that the client can use that specific IP address for a particular period of time.

The server can also end a NACK if it feels that the device should not use that IP address.

The entire process will be fast and a user does not need to know the technical details on how to receive an IP address from a DHCP server.

Tip: You can visit Microsoft’s DHCP Basics page to have a proper idea about the different packets.

What are the pros and cons?

Pros

  • Any device including a computer that connects to a local network or internet needs to be properly configured to ensure communication on that network. As the configuration will be automatic with DHCP, it can be used for almost all types of devices such as the gaming consoles, switches, and computers.

  • The possibility of same IP address for two devices will be less as there will dynamic IP address assignment. That will be very convenient while using static IP addresses, and manually assigned addresses.

  • The network management will be easier than ever. All the devices of a network will get a specific IP address and they can get the addresses automatically. The user can also consider an alternative that will manually assign the addresses to every single device on that network.

  • As the process will be automatic, the devices will be able to move from one network to another easily if all these devices are related to DHCP and have received an IP address automatically. That can be very helpful for the remote devices.

Cons

  • In most of the cases, a device that has an IP address given by a DHCP server will need to change the IP address every time when it joins the network. If it has received the IP addresses manually, then the process will be time-consuming. If it is manually assigned, then it needs to be manually unassigned so that any other device will be able to use that specific IP address. As it will be manually, there are the possibilities of human error and it will take longer as well.

  • There are many benefits of using DHCP. But at the same time, it might not be a good option for all types of the businesses. It will not be ideal for those businesses that demand constant access such as the file servers and printers.

  • It might not be a good option for the devices that work in the offices to offer an ever-changing IP address. It will make the process complicated. For example, if a printer needs to change the IP address then all devices connected to that printer need to update their settings regularly to use the printer.

  • You can avoid this by not using DHCP for these types of devices. Instead, you can consider using static IP address.

  • The same is applicable to the permanent remote access to a device or computer in your home network. If it has DHCP setup, then your computer will get a new IP address at some point in time and you will not be able to access your computer. While using remote access software with IP address-based access, you can consider using a static IP address for your computer for an easy accessibility.

Additional things on DHCP

  • A DHCP server is designed to define a range or scope of an IP address. It enables a device to get a valid network connection.

  • DHCP is considered very useful due to a number of reasons. It enables many devices to connect to a network for a particular period of time without relying on a massive pool of available IP addresses. For instance, if a DHCP server has given only twenty addresses, even fifty and more devices will be able to connect to the network when only 20 (not more than 20) devices are using one of the addresses concurrently.

  • DHCP offers a specific IP address for a particular period of time. Therefore, if you use commands such as ipconfig to find the IP address of your computer, it will offer different results over a period of time.

  • DHCP is used to get dynamic IP addresses, but it does not prove that you cannot use static IP addresses at the same time. Different devices with dynamic IP addresses and manually assigned IP address will be able to co-exist on the same network. You can use both of them without any difficulty.

  • We know that ISP utilizes DHCP to issue IP addresses. You can also see it while identifying the public IP address. It will keep changing unless your network uses a static IP address.

  • In Windows, when a DHCP server fails to offer a functional an IP address to any device, the APIPA will assign a specific temporary IP address. It can use this address until it does not get a valid one.

  • DHCP is the creation of The Dynamic Host Configuration Working Group of the Internet Engineering Task Force.