DNSjärjestelmä

The DNSjärjestelmä, or Domain Name System, is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network. It translates human-readable domain names, like www.example.com, into machine-readable IP addresses, such as 192.0.2.1, which computers use to identify each other. This system is fundamental to the functioning of the internet, enabling users to access websites and online services without needing to remember complex numerical IP addresses.

When a user types a domain name into a web browser, their computer sends a request to a DNS resolver. This resolver then queries a series of DNS servers to locate the correct IP address associated with that domain name. The process involves several types of servers, including root servers, Top-Level Domain (TLD) servers, and authoritative name servers, each playing a crucial role in the hierarchical lookup. Caching by resolvers and servers also plays a significant part in speeding up the process by storing frequently accessed DNS information. Without the DNSjärjestelmä, the internet as we know it would be largely unusable, as navigating online resources would rely solely on memorizing IP addresses. Its reliability and efficiency are therefore paramount for global internet connectivity.