Domain Name System

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How the DNS routes traffic to a user's machine

The Domain Name System, or DNS, is a naming system for anything connected to the internet. Its primary use is to allow humans to use meaningful domain names, such as, in place of computer-readable IP address, such as Ethical concerns surrounding cyber squatting and spoofing have arisen and point to the need for consideration of ethical concerns that have not yet been discovered.


Internet Corporation for Assigned Names and Numbers (ICANN)

The Internet Corporation for Assigned Names and Numbers (ICANN) is a nonprofit organization that maintains DNS. ICANN is responsible for allocating IP address spaces, overseeing top-level domains, and creating Internet related policy [1]. ICANN has designated seven “keys” to different security experts around the world. As a security failsafe, five of the seven key holders can reset the Domain Name System in the event of an emergency. These Recovery Key Share Holders include representatives from the United States, Trinidad and Tobego, China, Burkina Faso, Canada, and the Czech Republic[2].


A domain name is made up of several parts called ‘’labels’’, separated by periods. The right most label in a domain name is associated with the top level domain, or ‘’TLD’’. Subsequent labels to the left are additional sub-domains of the top level domain[1].

For instance, in "", "edu" is a top level domain to which "umich" is a subdomain, with "ctools" being a subdomain of “umich”.

Top Level Domains

Every domain name ends with a top level domain. These are labels such as ".edu" ".org" and most commonly ".com".

There were seven original generic top level domains as well as 2-character country designation codes. The original and common seven are:

  • ".gov" for government websites
  • ".mil" for military websites".com" for commerce websites
  • ".edu" for education-associated websites
  • ".org" for organization's websites
  • ".net" for networks
  • ".int" for international websites.[2]

Second Level Domains

A domain name can have a limitless number of sub-domains. As in the example "", "umich" is a subdomain of "edu" where "ctools" is a subdomain of "umich." The preceding element in a domain name, such as "www" indicates the host server function. For instance "" provides a specific function that is different from ""


Individuals and corporations must register their domain names through certified ICANN registrars. Domain registrations are completed in a yearly cycle. Microsoft's Developer Network Series states "Domain registrations can be transferred from one domain registrar to another. If the domain registration isn't renewed, the domain name becomes publicly available"[3]. The Dallas Cowboys failed to renew their domain registration and suffered consequences publicly. In 2010 the Cowboys domain expired and was purchased by an individual who changed the site to a picture of two boys playing soccer and contact information regarding future purchase of the domain[4].


2016 Dyn Cyberattack

On October 21, 2016, DNS service provider Dyn was taken down in the largest distributed denial-of-service (DDoS) attack ever recorded. The attack was conducted by the Mirai botnet, a network of Internet of Things (IoT) devices infected with Mirai malware. The attack restricted access to many websites that rely on Dyn services, including,,,, and Spotify[5].

Ethical Issues

Misleading Names

Since domain names are all lowercase and contain no spaces, inadvertent combinations of letters in an address have led to confusion. Such examples include "" for "Go Red Foxes", "" for Therapist Finder, and "" for "Mole Station Nursery". Similarly, typos of commonly visited sites can be registered to attract some of the traffic intended for the legitimate site. For instance, "" redirects a user to a Spanish webpage with adult content, as opposed to "" which would bring the user to Riot Games' popular League of Legends game.[3]


Cybersquatting is defined as "the registration of a commercially valuable Internet domain name, as a trademark, with the intention of selling it or profiting from its use."[6] Though less common now than in the beginning of the 'dot com' era, cybersquatting still occurs regularly. One notable case of (unintentional) cybersquatting was that of Mike Rowe and Microsoft.[7] While anticipating a game release or movie announcement, cybersquatters will purchase domains that they believe others will want to use legitimately to promote their product. Prior to the announcement of The Elder Scrolls: Skyrim, many domains related to the phrase 'Skyrim' were bought and squatted upon until people with a vested interest in the game were forced to purchase the domain from the squatter at a highly marked up rate.

Whether or not there is a reasonable way to stop this practice, outside of sending Cease and Desist notices to the squatters in question, has not been decided. It is a practice that is still in full swing today, and is one of the disadvantages of the domain name system that is in place today.

Cache Poisoning

Also known as DNS spoofing, cache poisoning is the effort to direct internet traffic away from legitimate servers and toward servers that benefit nefarious or illegal interests. A hacker who gains control of a DNS server can alter information so that when utilized, a search to a specific DNS will take the user to a server unrelated to the one that the user originally intended.

Cache poisoning can spread if ISP’s are receiving information from a compromised DNS server. The poisoned cache information then infects a user's home router and personal computer as users look up and store poisoned information [8].