The domain name system (DNS) is a hierarchical database that can be viewed as a tree structure. The tree structure creates a search path to the right name server. This search path is used to resolve a domain name into the corresponding IP address so that a computer connected to the internet may communicate with another computer over the internet. For example, the IPv4 address of the domain name www.traficom.fi is 18.104.22.168.
DNS Tree Structure
The fi-zone is one of the many zones in the entire domain name system, each having the same structure.
The structure of the domain name system is like a tree. At the top of the tree, there is the top-level root. All top-level domains (TLD) are located under this root. Top-level domains are divided into country code top-level domains (ccTLD) and generic top-level domains (gTLD). The top-level root name servers have information on all top-level domain name servers.
Single domain names, i.e. second-level domains (SLD) are represented by the dots in the middle of the tree. Addresses for services are usually third-level domains (e.g. shop.vr.fi). Third-level domains are often also called subdomains.
A domain name reveals where the related information can be found in the tree structure. In the domain name www.traficom.fi, the amount of dots indicates the levels to the root, or the top level, of the DNS tree. The dot representing the root level is always located at the end of the domain name even though it is normally left out (e.g. www.traficom.fi. is written www.traficom.fi).
Fi-root name servers
The country code .fi has eight root name servers located around the world. Because of the multiple geographic locations, fi-domain names are 100% reliable. Finnish domain names, websites and emails ending with .fi operate reliably and return fast answers to queries anywhere in the world.
The Domain Name System is defined in the RFC documents 1034 and 1035.