The main purpose of a domain name is to provide symbolic representations, i.e., recognizable names, to mostly numerically addressed Internet resources. This abstraction allows any resource (e.g., website) to be moved to a different physical location in the address topology of the network, globally or locally in an intranet, in effect changing the IP address. This translation from domain names to IP addresses (and vice versa) is accomplished with the global facilities of Domain Name System (DNS).
By allowing the use of unique alphabetical addresses instead of numeric ones, domain names allow Internet users to more easily find and communicate with web sites and any other IP-based communications services. The flexibility of the domain name system allows multiple IP addresses to be assigned to a single domain name, or multiple domain names to be services from a single IP address. This means that one server may have multiple roles (such as hosting multiple independent websites), or that one role can be spread among many servers. One IP address can also be assigned to several servers, as used in anycast networking.
By allowing the use of unique alphabetical addresses instead of numeric ones, domain names allow Internet users to more easily find and communicate with web sites and any other IP-based communications services. The flexibility of the domain name system allows multiple IP addresses to be assigned to a single domain name, or multiple domain names to be services from a single IP address. This means that one server may have multiple roles (such as hosting multiple independent websites), or that one role can be spread among many servers. One IP address can also be assigned to several servers, as used in anycast networking.
Second-level and lower level domains
Below the top-level domains in the domain name hierarchy are the second-level domain (SLD) names. These are the names directly to the left of .com, .net, and the other top-level domains. As an example, in the domain en.wikipedia.org, wikipedia is the second-level domain.
Next are third-level domains, which are written immediately to the left of a second-level domain. There can be fourth- and fifth-level domains, and so on, with virtually no limitation. An example of a working domain with four domain levels is www.sos.state.oh.us. The www preceding the domains is a host name of the World-Wide Web server. Each level is separated by a dot, or period symbol. 'sos' is said to be a sub-domain of 'state.oh.us', and 'state' a sub-domain of 'oh.us', etc. In general, Sub-domains are domains subordinate to their parent domain. An example of very deep levels of subdomain ordering are the IPv6 reverse resolution DNS zones, e.g., 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa, which is the reverse DNS resolution domain for the IP address of a loopback interface, or the localhost name.
Second-level (or lower-level, depending on the established parent hierarchy) domain names are often created based on the name of a company (e.g., microsoft.com), product or service (e.g., gmail.com). Below these levels, the next domain name component has been used to designate a particular host server. Therefore, ftp.wikipedia.org might be an FTP server, www.wikipedia.org would be a World Wide Web server, and mail.wikipedia.org could be an email server, each intended to perform only the implied function. Modern technology allows multiple physical servers with either different (cf. load balancing) or even identical addresses (cf. anycast) to serve a single hostname or domain name, or multiple domain names to be served by a single computer. The latter is very popular in Web hosting service centers, where service providers host the websites of many organizations on just a few servers
Next are third-level domains, which are written immediately to the left of a second-level domain. There can be fourth- and fifth-level domains, and so on, with virtually no limitation. An example of a working domain with four domain levels is www.sos.state.oh.us. The www preceding the domains is a host name of the World-Wide Web server. Each level is separated by a dot, or period symbol. 'sos' is said to be a sub-domain of 'state.oh.us', and 'state' a sub-domain of 'oh.us', etc. In general, Sub-domains are domains subordinate to their parent domain. An example of very deep levels of subdomain ordering are the IPv6 reverse resolution DNS zones, e.g., 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa, which is the reverse DNS resolution domain for the IP address of a loopback interface, or the localhost name.
Second-level (or lower-level, depending on the established parent hierarchy) domain names are often created based on the name of a company (e.g., microsoft.com), product or service (e.g., gmail.com). Below these levels, the next domain name component has been used to designate a particular host server. Therefore, ftp.wikipedia.org might be an FTP server, www.wikipedia.org would be a World Wide Web server, and mail.wikipedia.org could be an email server, each intended to perform only the implied function. Modern technology allows multiple physical servers with either different (cf. load balancing) or even identical addresses (cf. anycast) to serve a single hostname or domain name, or multiple domain names to be served by a single computer. The latter is very popular in Web hosting service centers, where service providers host the websites of many organizations on just a few servers
Resale of domain names
The business of resale of previously registered domain names is known as the "domain aftermarket".Various factors influence the perceived value or market value of a domain name. They include 1) the natural or "organic" traffic that can be attributed to web surfers typing in a domain name in their web browser as opposed to doing a search for the site through a search engine. 2) Branding Opportunity. The ability to have a term recognized and easily recalled as a brand for a company or entity. 3) Re-sale value. The ability to spot trends and predict the value of a name based on its length (short is preferred), clarity, and commercial use. The word loan is far more valuable than the word sunshine.Generic domain names have sprung up in the last decade. Certain domains, especially those related to business, gambling, pornography, and other commercially lucrative fields of digital world trade have become very much in demand to corporations and entrepreneurs due to their importance in attracting clients.The most expensive public sale of an Internet domain name to date, according to DNJournal, is porn.com which was sold in 2007 for $9.5 million cash.[citation needed]There are disputes about the high values of domain names claimed and the actual cash prices of many sales such as Business.com. Another high-priced domain name, sex.com, was stolen from its rightful owner by means of a forged transfer instruction via fax. During the height of the dot-com era, the domain was earning millions of dollars per month in advertising revenue from the large influx of visitors that arrived daily. The sex.com sale may have never been final as the domain is still with the previous owner. Also, that sale was not just a domain but an income stream, a web site, a domain name with customers and advertisers, etc. Two long-running U.S. lawsuits resulted, one against the thief and one against the domain registrar VeriSign [1]. In one of the cases, Kremen v. Network Solutions, the court found in favor of the plaintiff, leading to an unprecedented ruling that classified domain names as property, granting them the same legal protections. In 1999, Microsoft traded the name Bob.com with internet entrepreneur Bob Kerstein for the name Windows2000.com which was the name of their new operating system. [2]One of the reasons for the value of domain names is that even without advertising or marketing, they attract clients seeking services and products who simply type in the generic name. This is known as Direct Navigation or Type-in Traffic. Furthermore, generic domain names such as movies.com (now owned by Disney) or Books.com (now owned by Barnes & Noble) are extremely easy for potential customers to remember, increasing the probability that they become repeat customers or regular clients. In the case of Movies.com, Disney has built a stand-alone portal featuring branded content. More and more large brands are beginning to employ a more comprehensive domain strategy featuring a portfolio of thousands of domains, rather than just one or two.Although the current domain market is nowhere as strong as it was during the dot-com heyday, it remains strong and is currently experiencing solid growth again. [3] Annually tens of millions of dollars change hands in connection with the resale of domains. Large numbers of registered domain names lapse and are deleted each year. On average, more than 25,000 domain names drop (are deleted) every day.It is important to remember that a domain (name, address) must be valued separately from the website (content, revenue) that it is used for. The high prices have usually been paid for the revenue that was generated from the website at the domain's address (URL.). The intrinsic value of a domain is the registration fee. It is difficult to appraise a current market value for a domain. The Fair Market Value of a domain can be anything from nearly nothing to millions of dollars. Factors involved may include previous sales data of similar domains, however a single letter difference can completely alter the value. The value of the domain (or any sum resp. division etc.) are usually added to the current or expected revenue from the web content (advertising, sales, etc.). The price of a domain (name + ext.) should not be confused with that of a website (content + revenue).An estimate by an appraiser is always the addition of what they would like a domain to be worth together with the effective/expected/desired revenue from the web content. Some people put value on the length of the SLD (name) and other people prefer description capability, but the shorter an SLD is, the less descriptive it can be. Also, if short is crucial, then the TLD (extension) should be short too. It is less realistic to get a domain like LL.travel or LL.mobi than a domain travel. LL or mobi. LL. This illustrates the relativity of domain value estimation. It is safe to say that the revenue of web (content) can be easily stated, but that the value of a domain (SLD.TLD aka name.ext) is a matter of opinion and preference. In the end, however, any sale depends on the expectations of the domain seller and the domain buyer.A webmaster creating a new web site either buys the domain name directly from a domain name registrar, or indirectly from a domain name registrar through a domainer. People who buy and sell domain names are known as domainers. People who sell value estimation services are known as appraisers.
Examples
The following example illustrates the difference between a URL (Uniform Resource Locator) and a domain name:
URL: http://www.example.net/index.html
Domain name: www.example.net
Registered domain name: example.net
As a general rule, the IP address and the server name are interchangeable. For most Internet services, the server will not have any way to know which was used. However, the explosion of interest in the Web means that there are far more Web sites than servers. To accommodate this, the hypertext transfer protocol (HTTP) specifies that the client tells the server which name is being used. This way, one server with one IP address can provide different sites for different domain names. This feature goes under the name virtual hosting and is commonly used by web hosts.
For example, as referenced in RFC 2606 (Reserved Top Level DNS Names), the server at IP address 208.77.188.166 handles all of the following sites:
URL: http://www.example.net/index.html
Domain name: www.example.net
Registered domain name: example.net
As a general rule, the IP address and the server name are interchangeable. For most Internet services, the server will not have any way to know which was used. However, the explosion of interest in the Web means that there are far more Web sites than servers. To accommodate this, the hypertext transfer protocol (HTTP) specifies that the client tells the server which name is being used. This way, one server with one IP address can provide different sites for different domain names. This feature goes under the name virtual hosting and is commonly used by web hosts.
For example, as referenced in RFC 2606 (Reserved Top Level DNS Names), the server at IP address 208.77.188.166 handles all of the following sites:
- example.com
- www.example.com
- example.net
- www.example.net
- example.org
When a request is made, the data corresponding to the hostname requested is provided to the user
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