What is the DHCP port number?

Hello everyone,

Are you still worrying about the port number of DHCP? Today, this article will bring you the port number of DHCP, the port number of DNS, and the port number of other commonly used protocols.

What is the DHCP port number?

The DHCP protocol adopts a client/server model, and the task of dynamically assigning host addresses is driven by network hosts. When the DHCP server receives the address information from the network host, it will send the relevant address configuration and other information to the network host, so as to realize the dynamic configuration of the address information of the network host.

The DHCP protocol uses UDP as the transport protocol and uses UDP 67/68 ports. The host sends a request message to port 68 of the DHCP server, and the DHCP server responds with a reply message to port 67 of the host.

DHCPv6 packets are carried over UDPv6 using UDP ports 546/547. The UDP destination port number that the client listens on is 546. The UDP port number monitored by the server and relay agent is 547.

Picture 1 DHCP process

What is the DNS port number?

The DNS port number is 53. DNS can use both TCP and UDP transport protocols. However, due to its simplicity and speed, the UDP-based protocol is generally used.

TCP provides stability during DNS resolution. With TCP 53, no data will be lost in transmission over the network, which will make DNS services more stable. But this imposes some overhead on the server and client.

The most widely known protocol used for DNS is UDP 53. Most DNS servers use UDP port 53, which simplifies operations and reduces resource usage.

Common protocol port numbers

That is all I want to share with you! I hope it helps you!