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This article mainly introduces the working principle of DHCP analysis, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let the editor take you to understand it.

DHCP dynamic host configuration protocol: the protocol used by computers to obtain configuration information. DHCP allows a computer to be assigned an IP address without requiring the manager to configure information about the computer in the server data. The function of DHCP is to assign an IP to PC. In a local area network, if your routing has this function, it will remember the MC address of the PC, then assign an IP address to the PC, and then the PC of the MC address will use this IP address to surf the Internet later, the function is to prevent foreign PC from surfing the Internet, and avoid errors caused by the repeated use of IP addresses.

1. The client uses broadcast packets to send DHCP requests:

When the DHCP client is set to obtain IP automatically, boot or restart will automatically send broadcast packets to all computers in the physical network segment. The destination IP of this packet is 255.255.255.255. If there is no DHCP server in the network segment, other computers will discard the packet. If there is a DHCP packet, it will respond.

2. Response of DHCP server:

When the DHCP server receives the request from the client, it will work against the MAC of the client and its own network setting data. First of all, it will go to the log file of the server to query whether the client has ever used an IP, and if an IP has been used and is still free, the IP will be assigned to the client. Secondly, if the MAC address of this client is bound to an IP address, then assign this IP to the client. If the first two are not, the IP with high-to low-order real free will be automatically assigned to the client. In addition, the client is given a lease time and waits for a response from the client.

3. The client modifies the network environment:

After receiving the IP and parameters assigned by DHCP, the client sets its own network environment, and then sends an acknowledgement packet to the DHCP server to acknowledge receipt.

4. The DHCP server confirms and records:

When the DHCP server receives the confirmation received by the client, it also confirms and completes the IP assignment task and establishes the lease behavior to record in its own log file. When the client goes offline, restarts, shuts down, or the lease expires and the client does not reapply to the DHCP server, the DHCP server will reclaim the IP and put it back in its IP address pool to wait for backup.

Thank you for reading this article carefully. I hope the article "Analysis of the working principle of DHCP" shared by the editor will be helpful to everyone. At the same time, I also hope that you will support us and pay attention to the industry information channel. More related knowledge is waiting for you to learn!

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