Which protocol is used to automate IP configuration including IP address, subnet mask, default gateway, and DNS information?

The correct choice utilizes the Dynamic Host Configuration Protocol (DHCP), which serves a crucial role in network management by automating the process of IP configuration for devices on a network. DHCP simplifies network setup by allowing devices to obtain various network settings automatically, including their assigned IP address, subnet mask, default gateway, and DNS server information, without the need for manual configuration.

When a device connects to a network, it sends a broadcast request for IP configuration. A DHCP server responds to this request with the necessary information, empowering devices to communicate effectively over the network. This automation significantly reduces configuration errors and administrative overhead, making the deployment of devices in larger networks much more efficient.

Other protocols mentioned serve different purposes: Simple Network Management Protocol (SNMP) is used for network management and monitoring, Address Resolution Protocol (ARP) is used for mapping IP addresses to MAC addresses, and Simple Mail Transfer Protocol (SMTP) handles the sending of emails. Each serves critical functions within network communication, but they do not facilitate the automatic configuration of IP settings in the way DHCP does.