What is the function of the application using UDP port 68?

The function of the application using UDP port 68 is associated with the Dynamic Host Configuration Protocol (DHCP) as a client. When a device, such as a computer or smartphone, connects to a network, it often requires configuration parameters such as an IP address, subnet mask, gateway, and DNS servers. This configuration is typically managed through DHCP.

In this context, the client device sends DHCP discovery messages to locate a DHCP server. These messages are sent to the broadcast address using UDP port 67, where the DHCP server listens for requests. Once the server responds, the client listens for the configuration replies on UDP port 68. The communication is essential because it allows the client to receive the necessary network configurations from the server without manual input, facilitating seamless network connectivity.

By understanding this, we recognize that port 68 is specifically reserved for the responses from the DHCP server to the client, solidifying the relationship between the ports and the roles they play in the DHCP process.