Which protocol is used for resolving domain names into IP addresses?

The protocol that is specifically designed for resolving domain names into IP addresses is the Domain Name System (DNS). This system plays a crucial role in the functioning of the internet, as it allows users to access websites using human-readable domain names (like www.example.com) instead of having to remember numeric IP addresses (such as 192.0.2.1).

When a user types a domain name into a web browser, the DNS protocol is invoked to translate that domain name into the corresponding IP address, enabling the connection to the correct server. This translation process is essential for locating and accessing resources on the internet efficiently.

Other protocols mentioned have their respective roles but do not perform name resolution. For instance, Internet Control Message Protocol (ICMP) is primarily used for sending error messages and operational queries, the Dynamic Host Configuration Protocol (DHCP) is responsible for automatically assign IP addresses to devices on a network, and Address Resolution Protocol (ARP) is used to map IP addresses to physical MAC addresses on a local network. These functions are vital for network operations, but they do not facilitate the translation of domain names to IP addresses like DNS does.