The Domain Name System (DNS)

Programs could use network (e.g., IP) addresses to refer to Web pages and other resources, but these addresses are difficult to remember and update. High-level, readable names like www.cs.washington.edu were introduced to solve this issue, requiring a mechanism to convert these names to network addresses. 

 

Initially, a file called hosts.txt was used to map names to addresses, but this became impractical as the Internet grew. To address scalability and conflict issues, the Domain Name System (DNS) was created in 1983. DNS employs a hierarchical, domain-based naming scheme and a distributed database to map host names to IP addresses. When an application needs to find an IP address, it uses a resolver to query a local DNS server, which returns the IP address, enabling the application to establish a connection.

DNS Name Space

Handling a vast and ever-evolving collection of names is a complex issue.

Within the postal system, the process of managing names is accomplished by mandating that letters include the country, state or province, city, street address, and the name of the recipient, either directly or indirectly. 

By employing hierarchical addressing, any potential ambiguity between the Marvin Anderson residing on Main St. in White Plains, N.Y. and the Marvin Anderson residing on Main St. in Austin, Texas is eliminated. 

 

The Domain Name System (DNS) operates in a similar manner.

ICANN (Internet Corporation for Assigned Names and Numbers) is the body responsible for managing the highest level of the naming hierarchy on the Internet. 

 

The Internet is conceptually divided into more than 250 top-level domains, with each domain encompassing multiple hosts. The domain is divided into subdomains, which are then subdivided, and so on.

Each of these domains can be depicted as a hierarchical structure. The leaves of the tree symbolize domains that lack subdomains, but they may have computers. A leaf domain can either consist of a solitary host or include a firm with a multitude of hosts. 

 

There are two types of top-level domains: generic and country-specific. 

 

The generic domains consist of both original domains from the 1980s and domains that were introduced through petitions to ICANN. Additional generic top-level domains will be incorporated in the future. 

 

The nation domains consist of one entry for each country, as described in ISO 3166. Non-Latin alphabets were first implemented for internationalized country domain names in 2010. These domains allow individuals to assign names to hosts using Arabic, Cyrillic, Chinese, or other non-English languages.

Acquiring a second-level domain, such as name-of-company.com, is a simple task. 

Registrars appointed by ICANN manage the top-level domains. 

To obtain a name, one must simply visit the appropriate registrar (in this case, for com) to verify if the desired name is both available and not already registered as someone else's trademark. Assuming no issues arise, the individual making the request will compensate the registrar with a modest yearly payment in order to obtain the desired name.

Nevertheless, with the increasing commercialization and globalization of the Internet, conflicts have arisen, particularly in the realm of name.

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Happy Exploring!