Dynamic Host Configuration Protocol (DHCP) is a network management protocol that helps the users of network services, such as DNS, NTP, and all networking protocols based on UDP or TCP, to simplify the process of configuring devices on IP network networks. A DHCP server assigns an IP address and other configuration network parameters for each network system to connect in a complicated way with other IP networks. The DHCP is an update to an earlier BOOTP protocol.
Components of DHCP
Here are the components of DHCP to explain how it works.
- DHCP server: This is a computer that runs DHCP and includes IP addresses and similar settings. It's usually a server or router, but anything like an SD-WAN system can be used as a host.
- DHCP client: This is the endpoint receiving DHCP server configuration information. This can be a monitor, handheld unit, IoT terminal, or something else that needs network access. Any of the DHCP information is optimized for default reception.
- Subnet: It is possible to break IP networks into subnets segments. Networks help ensure manageability in networks.
DHCP relay: This is a router or host which listens to client messages on the network and then transmits them to a configured server. The server returns answers to the relay handler, who transmits them to the recipient. This is good for centralizing DHCP servers instead of providing a node on a single subnet.
- Lease: This is the period during which a DHCP client keeps the IP address. The user must extend a contract if it expires.
How does DHCP work?
DHCP operates on the app layer to assign an IP address to the client dynamically, and this takes place through the sharing of the DHCP transactions or DHCP conversation string.
- DHCP Discovery: The DHCP client transmits DHCP server messages. The client machine will send a package with 255.255.255.255 or, if configured, a particular subset of the broadcast address. 255.255.255.255 is a special address for broadcasting that indicates "the network" that helps you to transmit a broadcast packet to your related network.
- DHCP Offer: The message of DHCP Discover is transmitted to the client by sending the DHCP message, and the DHCP server gives the client an IP address (form IP address pool). This message contains the proposed DHCP client IP address, default gateway, client MAC address, server IP address, subnet mask, and lease information.
- DHCP Request: In most instances, the client may receive several DHCP services since many DHCP servers operate in the network. If one server's IP address fails, other servers may backup the IP address. However, only one DHCP bid is approved by the customer. The client will forward a DHCP request to the offered address on one of the DHCP servers in reaction to the offer. The remaining DHCP servers also deleted all other IP addresses provided and returned them to the pool of available IP addresses.
- DHCP Acknowledgment: The server sends a confirmation to the client about the DHCP lease confirmation. Each other configuration requested by the client can be submitted by the server. The initialization of the Protocol is finished at this stage and the new Interface configurations are visible to the client.
Why it is important to use DHCP servers
- Proper IP configuration: The setting of IP address parameters must be correct, and an error can be made when working with inputs like "192.168.159.3." Typological errors are usually incredibly difficult to fix with the risk reduced by the use of a DHCP server.
- Mitigated IP address conflicts: An IP address is required for each connected computer. However, a repeat address may be used only once,, and there is a conflict where one or both computers are not related. This could be possible when manually allocated addresses are provided, especially when several endpoints, including mobile devices, are linked only periodically. By using DHCP, each address is used only once.
- Automation of IP address administration: Without DHCP, network administrators will have to manually allocate and cancel emails. Keeping track of which system has what address can be a futile activity, when devices need network connectivity and when they leave is almost impossible to understand This can be streamlined and centralized by DHCP so that network professionals are able to handle all locations from one position.
- Efficient change management: DHCP makes moving addresses, scopes, or endpoints very convenient. For example, a company may want the IP address scheme to be modified from range to range. This latest information is configured to the DHCP server, and the information is distributed to new endpoints. Similarly, no network setup is appropriate if a network system has been upgraded and replaced.