 |
Domain Name Industry Briefs
|
Volume 1, Issue1, February 2004
The VeriSign Domain Name Primer
Download
PDF
As the leading global domain name registry,
VeriSign closely monitors the state of the domain name market through
a variety of analytical and statistical research. This brief provides
a primer on the Domain Name System (DNS), domain names and the key players
in the industry.
Executive Summary
With over 580 million users globally, the Internet
is the fastest growing technology of the past decade or any other decade
before. According to Business Week, it took radio 30 years to reach
60 million people and television 15 years; the Internet has grown to
almost 10 times this size in a much shorter period of time.
A domain name is key to doing just about anything
on the Internet, from setting up a Web site to sending and receiving
email to building an online store. Today there are over 60 million registered
domain names. The Domain Name System (DNS), which supports these names,
is the engine that makes the Internet simple and accessible for users
around the world. The DNS is not just important to the smooth running
of the Internet but it also plays a very important part in everyday
life. Visits to the ATM machine, paying for groceries with your credit
card, placing a long-distance telephone call, would not be possible
if the DNS was not functioning. These activities rely on the Internet
or Internet technology, and the DNS is a fundamental part of the Internet:
without DNS, the Internet doesn't work.
And yet, for too many people, the DNS belongs
in the confusing realm of the technical experts. This primer provides
an overview of how the Domain Name System works and why it is so important
for the continued operation of the Internet.
The Domain Name System
The Domain Name System performs the simple,
straightforward function of mapping names to Internet Protocol (IP)
addresses and back. Every server on the Internet has an IP address,
represented as a series of four numbers separated by dots (e.g. 123.45.67.254).
But, like telephone numbers, these long series of numbers can be difficult
to remember. The DNS allows people to use names, instead of numbers,
to reach Web sites and send email messages.
The rightmost label in a domain name (such
as .com
or .net)
is referred to as the top-level domain or TLD. There are many TLDs available.
The DNS forms a hierarchy: each TLD has many second-level domains (e.g., abc
in www.abc.com);
each second-level domain can have many third-level domains (e.g., corporate
in corporate.abc.com)
and so forth. Recent changes allow domain names to use characters from
many different scripts, such as Kanji and Arabic, and not just the familiar
Latin alphabet used by English speakers.
After a user enters a domain name into a Web
browser, a behind-the-scenes process called resolution uses a global
network of name servers to look up the IP address corresponding to the
domain name. Web browsers and other applications need IP addresses and
not names to contact the appropriate Web server and retrieve the right
Web page. (See the chart below). The technology, servers, guidelines
and processes that make up these name servers form the backbone of the
DNS. The DNS is the low-level protocol that enables communications over
the Internet for applications like credit card processing, bank transactions
and telephony as well as Web browsing and email.
Domain Name System
Registration of Domain Names
Name servers for TLDs, such as .com and .net, route requests to lower-level name servers for ultimate
resolution. For example, the .com name servers refer queries about the verisign.com domain to VeriSign's name servers. Second-level
domains, such as versign.com, must be registered with the TLD operator. Domain
names can be registered through one of the hundreds of registrars and
thousands of resellers. With multiple channels available to register
names, it is simple for users to find the right combination of product,
price and complementary services to meet their needs. For example, many
registrars will let users register names with different top-level domains.
They also provide email services and even assist with building a Web
site.
The Top-Level Domains
There are over 250 top-level domain names of
varying types:
- Two-letter TLDs
(.uk, .de, .jp,
etc) correspond to the official two-letter abbreviations of over 240
countries and territories. These domains are called country-code TLDs
or ccTLDs for short. Each has a designated registry that operates the
domain according to local policies (for example, to register a name
in some TLDs you must be a local resident).
- Sponsored generic
TLDs (gTLDs) include .edu, .gov, .int, .mil, .aero, .coop, and .museum. A sponsored TLD is a specialized domain with a sponsor
representing the narrower community that the TLD serves.
- Unsponsored generic
TLDs (gTLDs) are .com, .net, .org, .biz, .info, .name and .pro. Unsponsored TLDs operate without any sponsoring organization
and generally have fewer restrictions for registrations than sponsored
TLDs.
How Registration Works
A user wanting to register a domain name contacts
a registrar. (Registrars are companies that sell domain names to end
users - there are currently over 150 registrars, located all over the
world, who sell domain names in .com and .net.) Upon receiving a users requested domain name, the registrar
first verifies that the name is available by checking with the registry
that manages the corresponding TLD. If the name is available, the registrar
registers the name with the registry, which adds the name to its database.
Now no one else can register that domain name during the term of the
registration.
How Resolution Works
Everyday, billions of users surf the Web and
send email using domain names instead of unfriendly and hard-to-remember
IP addresses. Between the time a user types a domain name into a browser
and when the Web page loads, a critical, time-sensitive process called
resolution occurs behind the scenes. For each request, the computer
checks first with the local name server to see if it recognizes the
domain name; if it doesn't, the local name server will check a root
name server, a TLD name server and finally the name server for the domain
itself. The entire process happens in a few tenths of a second and is
transparent to the end user.
With explosive growth in name registrations,
Web site resolutions and email usage, assuring the continued stability
and security of the DNS infrastructure is critical to anyone with an
interest in the Internet. (See the VeriSign
Domain Report for statistics on the growth in the domain
name industry).
How Resolution
Works
Source: VeriSign
A Bit of History
The Internet owes its roots to an ambitious
1973 research program of the U.S. Defense Advanced Research Projects
Agency (DARPA) to develop communication protocols that would allow networked
computers to communicate transparently across multiple linked packet
networks. With significant success and rapid growth, by the 1980s the
population of users expanded to include commercial enterprises and organizations
outside the U.S., in addition to government facilities.
In 1984, the Domain Name System was introduced.
Some of the earliest domain names in the system were symbolics.com,
mit.edu, think.com, css.gov and mitre.org. The U.S. Department of Defense
oversaw the domain name system until 1993, when the non-military component
of the system was privatized through a cooperative agreement between
the National Science Foundation and Network Solutions, Inc., among others.
Today the Internet functions as collaboration
among many cooperating parties. The Internet Corporation for Assigned
Names and Numbers (ICANN), a non-profit, private-sector corporation,
was established in 1998 by the U.S. Department of Commerce as the technical
coordination body for aspects of the Domain Name System.
Domain Name Timeline
1983:
Name server developed at University of Wisconsin, no longer requiring
users to know the exact path to other systems
1984:
Domain Name System (DNS) introduced
Number of hosts breaks 1,000
1985:
ISI at USC assumes responsibility for DNS root management
Symbolics.com becomes the first registered domain name on 15 March
Other firsts: cmu.edu, purdue.edu, rice.edu, berkeley.edu, ucla.edu,
rutgers.edu, bbn.com (24 Apr); mit.edu (23 May); think.com (24 May);
css.gov (June); mitre.org, .uk (July)
1987:
Number of hosts breaks 10,000
1989:
Number of hosts breaks 100,000
1990:
First commercial provider of Internet dial-up access (world.std.com)
1992:
Internet Society (ISOC) is chartered (January)
Number of hosts breaks 1,000,000
Term "surfing the Internet" coined
1993:
InterNIC created by National Science Foundation
Network Solutions, Inc awarded cooperative agreement for registration
services
1995:
$50 annual fee instated for domain names registration
1996:
Domain name tv.com sold to CNET for US$15,000
1997:
Domain name business.com sold for US$150,000
101,803 name servers in Whois database
1998:
Network Solutions registers its 2 millionth domain on 4 May
Compaq pays US$3.3million for altavista.com
ICANN established to transition DNS technical coordination from government
to private sector
1999:
First testbed registrars announced for competitive Shared Registry System
Register.com is first registrar to come online
business.com is sold for US$7.5million (it was purchased in 1997 for
US$150,000)
2000:
Testbed allowing registration of domain names in Chinese, Japanese and
Korean begins
ICANN selects new TLDs: .aero, .biz, .coop, .info, .museum, .name, .pro
(16 Nov)
2001:
EDUCAUSE takes over management of .edu domain
.biz, .info and .aero registrations begin
2003:
Public Interest Registry (PIR) takes over management of .org domain
Source: Hobbes' Internet Timeline
Copyright 2004 Robert H. Zakon
www.zakon.org/robert/internet/timeline/
Keeping the DNS Safe and Sound
With over 10 billion transactions a day, making
sure that the DNS works accurately, quickly and securely is a key factor
in maintaining the integrity of the Internet. VeriSign has a long history
of leadership with the DNS and has been the registry for the .com and
.net domains since the early nineties.
To provide redundancy and speed, VeriSign operates
13 .com and .net name server sites around the world at important Internet
hubs in North America, Europe and Asia. This "constellation"
of name servers is maintained, monitored and managed by VeriSign's team
of DNS experts. Each site in the constellation is well connected with
high bandwidth and tight security controls. To meet the exceptional
requirements of serving .com and .net, VeriSign developed its own proprietary
name server called ATLAS (Advanced Transaction Lookup And Signaling
System), which handles DNS traffic faster and more efficiently than
any commercially available option. For the past 7 years VeriSign's DNS
constellation has resolved every DNS query with 100% accuracy.
The Future of DNS
VeriSign is also a leader in DNS research and
development. The ATLAS name server platform allows changes to quickly
propagate throughout the DNS constellation: coming soon, newly registered
domain names will be visible in DNS within minutes instead of hours.
VeriSign is also planning to increase the security of DNS by implementing
the DNS security extensions, known as DNSSEC, developed by the Internet
Engineering Task Force (IETF). DNSSEC uses cryptography and digital
signatures to eliminate spoofing and increase security.
Definitions
TLD: Top Level Domain (rightmost label in a domain name)
Domain Name: using words instead of numbers to represent an
Internet address
Root Server: database with comprehensive name listings of Top
Level Domains
Whois: look-up directory to determine who registered which
domain names
Constellation: network of distributed name servers
Resolution: process that returns a web page after a name is
entered into a browser or sends/receives an email after a name is entered
in an email address
Learn More
Subscribe
or access the archives for the Domain Name Industry Briefs.
Send an email with your comments or questions to domainbrief@verisign.com.
About VeriSign
VeriSign, Inc. (Nasdaq: VRSN), delivers critical
infrastructure services that make the internet and telecommunications
networks more intelligent, reliable and secure. Every day VeriSign helps
thousands of businesses and millions of consumers connect, communicate,
and transact with confidence.
©2004 VeriSign, Inc. All rights reserved.
VeriSign, the VeriSign logo, The Value of Trust, and other trademarks,
service marks, and logos are registered or unregistered trademarks of
VeriSign, Inc. and its subsidiaries in the United States and in foreign
countries. 2/04
|
Worldwide Sites
