Before we begin explaining what is a DHCP reservation, we will simplify all the terms that might be confusing to many people.
As DHCP experts are the authors of this article, you can expect only high-quality content that will provide you with the most efficient answers and guidance for a successful DHCP reservation.
Then, after going through every piece of information we provide in this article, you will be able to handle the DHCP reservation process as a professional yourself. This means you will not need to go from forum to forum to figure out the complexity of the DHCP; instead, you will be able to successfully implement the knowledge you gained from this article.
So, without further ado, let’s dive into the world of IP and its connection to the DHCP reservation.
History of the DHCP
In 1984, the need for the configuration of simple devices appeared due to the increased number of diskless stations. To satisfy the needs of the fast-growing technological industry, computer engineers came up with the Reverse Address Resolution Protocol (RARP).
This protocol worked fine and accomplished the goals for which it was created, but the acting in the data link layer made its implementation difficult on many server platforms. The problem was that when it came to the data link layer, the Reverse Address Resolution Protocol required a server to be always present on each network link.
To overcome this new problem, the engineers devised a solution called Bootstrap Protocol (BOOTP) in September 1985.
This concept of the so-called relay agent was the highest advancement as it allowed the forwarding of Bootstrap Protocol (BOOTP) packets across different networks, meaning it allowed for one central BOOTP server to serve many hosts on many IP subnets.
The creation of the Dynamic Host Configuration Protocol (DHCP)
The revolutionary discovery and innovation of the Bootstrap Protocol was the inspiration behind the DHCP, with the difference that the DHCP can dynamically allocate different IP addresses from a pool and, most importantly, reclaim them when they are no longer in use.
Another fantastic perk of DHCP is that people can utilize it to deliver a wide range of additional configuration parameters to IP clients. This includes platform-specific parameters as well.
The DHCP was first introduced in October 1993, but due to some technical errors and problems, it was reissued shortly after. As of 2021, with a few updates, this protocol remains the ultimate core of the standard for all IPv4 networks.
Overview of the IP and DHCP
The simplest definition of IP is that this abbreviation stands for Internet Protocol. Its function is to define how devices communicate across and within the local networks on the Internet.
The moment when DHCP and IP cross is when the DHCP server manages IP settings on its local network, for instance, when the DHCP automatically and dynamically assigns IP addresses to those devices.
Unlike other protocols of this type, the DHCP’s operations are based on a client-server model, meaning when a device such as a computer connects to a network, this DHCP client software sends a broadcast query and requests the necessary information.
The most important thing you need to know about DHCP is that its server manages a lot of IP information and addresses the client configuration parameters, such as the name servers, default gateway, time servers, domain names, etc.
Methods Through Which DHCP Allocates IP Addresses
To better understand the DHCP reservation, we must first look at the methods DHCP uses to allocate the IP addresses.
- Automatic allocation – In the automatic allocation, the DHCP server permanently assigns a certain IP address to a client from the range defined by the administrator that requests an IP address. In this method, the DHCP server keeps a table of recently utilized IP address assignments to successfully assign the client the same IP address it previously had.
- Manual allocation – This method is known by many other names, such as reservation, static DHCP allocation, MAC/IP address binding, fixed address allocation, etc. This method works in a way that the administrator maps a unique identifier for each client to an IP address.
- Dynamic allocation – This allocation is based on a lease concept that there is a request-and-grant process through which the network administrator reserves a range of IP addresses for DHCP.
What Is a DHCP Reservation?
The principal reason the Dynamic Host Configuration Protocol was created is to dynamically configure host networking configuration on the go for easier deployment. The simplest explanation for this definition is that when a device such as a computer, for example, that was previously configured to use DHCP, reaches out to the network, the DHCP server’s job is to immediately provide and assign an IP address for the particular computer to utilize.
When it comes to home networks, in almost 99% of the cases, almost every device and computer will get its IP address from the DHCP that is running on the router.
On the other hand, when it comes to business networks, every device and computer that is not hosting services will get a suitable IP address from the DHCP server, which runs on their designated routers and servers.
Here is when the DHCP reservation comes into action. As DHCP servers support the DHCP reservation, you can provide a pre-set IP address on a specific client, which must be on its physical MAC address.
In other words, this means that the particular device or computer will always get the same IP address; that is, it will never change.
Read more: What Is A WiFi Dongle?
Where Are the DHCP Reservations Used?
- Printers
- IP phones
- Wireless access points
- Zero clients
- IoT devices
- IP PBX systems
Pros
- Ability to create different PXE boot environments
- Ability to change IP addresses expressly from a single console
- Manage IP addresses for third-party devices that otherwise you never have access to modify
- Manage IP addresses and IP reservations from a single console
- Manage network topology for ROBO efficiently and easily
Cons
- In cases when rogue DHCP servers appear on your network, the communication might get disrupted
- The computer or device must support DHCP configuration
- The device will have to rely on the DHCP server once you set it to use DHCP; if this server is down, so will the device
Conclusion
Well, this is it. We hope that you have now cleared your doubts about what is DHCP reservation and how you can use it.