What Is The Internet?
The internet is the world’s most popular
computer network. It began as an academic research project in 1969, and became
a global commercial network in the 1990s. Today it is used by more than 2
billion people around the world.
The internet is notable for its
decentralization. No one owns the internet or controls who can connect to it.
Instead, thousands of different organizations operate their own networks and
negotiate voluntary interconnection agreements.
Most people access internet content
using a web browser. Indeed, the web has become so popular that many people
incorrectly treat the internet and the web as synonymous. But in reality, the
web is just one of many internet applications. Other popular Internet
applications include email and BitTorrent.
Where
Is The Internet?
The internet has three basic parts: the
last mile, data centers and the backbone.
The
last mile is
the part of the internet that connects homes and small businesses to the
internet. Most internet connections in are provided by cable TV companies such
as Comcast and Time Warner. The last mile also includes the towers that allow
people to access the internet with their cell phones. These users account for a
small but rapidly growing share of internet traffic.
Data
centers are
rooms full of servers that store user data and host online apps and content.
Some are owned by large companies such as Google and Facebook. Others are
commercial facilities that provide service to many smaller websites. Data
centers have very fast internet connections, allowing them to serve many users
simultaneously. Data centers can be located anywhere in the world, but they are
often located in remote areas where land and electricity are cheap. For
example, Google, Facebook, and Microsoft have all constructed vast data centers in Iowa.
The
backbone consists
of long-distance networks that carry data between data centers and consumers.
The backbone market is highly competitive. The internet backbone consists
primarily of fiber optic cables. Backbone providers frequently connect their
networks together at internet exchange points, usually located in major cities.
Who
Created The Internet?
The internet began as Advanced
Research Projects Agency Network (ARPANET),
an academic research network that was funded by the military’s Advanced
Research Projects Agency (ARPA, now known as DARPA). The project was led by Bob Taylor,
an ARPA administrator, and the network was built by the consulting firm of
Bolt, Beranek and Newman. It began operations in 1969.
In 1973, software engineers Vint Cerf and Bob Kahn began work on the next generation of
networking standards for the ARPANET. These standards, known as Transmission Control Protocol/Internet Protocol
(TCP/IP), became the foundation of the modern internet. ARPANET switched
to using TCP/IP on January 1, 1983.
During the 1980s, funding for the
internet shifted from the military to the National Science Foundation. The
NSF funded the long distance networks that served as the internet’s backbone
from 1981 until 1994. In 1994, the Clinton Administration turned control over the internet backbone to the
private sector. It has been privately operated and funded ever since.
Did
Al Gore Invent The Internet?
Former Vice President Al Gore is
frequently quoted as claiming credit for the invention of the internet, but
what he actually said in a 1999 CNN interview was “I took the initiative in creating
the internet.” Gore was widely mocked for this statement. But the men who did
invent the internet, TCP/IP designers Bob Kahn and Vint Cerf, wrote in Gore’s defense in 2000. They argue that Gore was “the
first political leader to recognize the importance of the internet and to
promote and support its development.”
“As far back as the 1970s Congressman
Gore promoted the idea of high speed telecommunications,” the pair wrote. “As a
Senator in the 1980s Gore urged government agencies to consolidate what at the
time were several dozen different and unconnected networks into an ‘Interagency
Network.’” Gore sponsored the 1991 High Performance
Computing and Communications Act, which Kahn and Cerf say “became
one of the major vehicles for the spread of the internet beyond the field of
computer science.”
Who
Runs The Internet?
No one runs the internet. It’s organized
as a decentralized network of networks. Thousands of companies, universities,
governments, and other entities operate their own networks and exchange traffic
with each other based on voluntary interconnection agreements.
The shared technical standards that make
the internet work are managed by an organization called the Internet Engineering
Task Force (IETF). The
IETF is an open organization; anyone is free to attend meetings, propose new
standards, and recommend changes to existing standards. No one is required to
adopt standards endorsed by the IETF, but the IETF’s consensus-based decision making
process helps to ensure that its recommendations are generally adopted by the
internet community.
The Internet Corporation for Assigned Names and Numbers (ICANN) is sometimes described as
being responsible for internet governance. As its name implies, ICANN is in
charge of distributing domain names (like vox.com) and IP
addresses. But ICANN doesn’t control who can connect to the internet or
what kind of information can be sent over it.
What’s
An IP Address?
Internet Protocol addresses are numbers
that computers use to identify each other on the internet. For example, an IP address
for vox.com is
216.146.46.10.
An ICANN department known as the Internet Assigned
Numbers Authority is
responsible for distributing IP addresses to ensure that two different
organizations don’t use the same address.
What
Is IPv6?
The current internet standard, known as Internet
Protocol Version 4 (IPv4), only allows for about 4 billion IP addresses. This
was considered a very big number in the 1970s, but today, the supply of IPv4
addresses is nearly exhausted.
So internet engineers have developed a
new standard called Internet Protocol
Version 6 (IPv6). IPv6 allows for a mind-boggling number
of unique addresses — the exact figure is 39 digits long — ensuring that the world will never
again run out of IP addresses.
But the transition to IPv6 has been
slow. Technical work on the standard was completed in the 1990s, but the
internet community has faced a serious chicken-and-egg problem: as long as most
people were using IPv4, there was little incentive for anyone to switch to
IPv6.
In the last couple of years, as IPv4
addresses have become scarce, IPv6 adoption has accelerated. The fraction of users who connected to Google via
IPv6 grew from about 1
percent at the beginning of 2013 to about 3.5 percent in June 2014. But it will
be many years before IPv4 can be retired.
How
Does Wireless Internet Work?
In its early years, internet access was
carried over physical cables. But more recently, wireless internet access has
become increasingly common.
There are two basic types of wireless
internet access: wireless fidelity (wifi) and cellular. Wifi networks are relatively simple. Anyone can
purchase wifi networking equipment in order to provide internet access in a
home or business. Wifi networks use unlicensed spectrum: electromagnetic
frequencies that are available for anyone to use without charge. To prevent
neighbors’ networks from interfering with each other, there are strict limits
on the power (and therefore the range) of wifi networks.
Cellular networks are more centralized.
They work by breaking up the service territory into cells. In the densest
areas, cells can be as small as a single city block; in rural areas a cell can
be miles across. Each cell has a tower at its center providing services to
devices there. When a device moves from one cell to another, the network
automatically hands off the device from one tower to another, allowing the user
to continue communicating without interruption.
Cells are too large to use the
unlicensed, low-power spectrum used by wifi networks. Instead, cellular
networks use spectrum licensed for their exclusive use. Because this spectrum
is scarce, it is usually awarded by auction. Wireless auctions have generated tens of
billions of dollars in
revenue for the US treasury since the first one was held in 1994.
What
Is The Cloud?
The cloud describes an approach to
computing that has become popular in the last decade. By storing files on
servers and delivering software over the internet, cloud computing provides
users with a simpler, more reliable computing experience.
Cloud computing allows consumers and
businesses to treat computing as a utility, leaving the technical details to
technology companies.
For example, in the 1990s, many people
used Microsoft Office to edit documents and spreadsheets. They stored documents
on their hard drives. And when a new version of Microsoft Office was released,
customers had to purchase it and manually install it on their PCs.
In contrast, Google Docs is a cloud
office suite. When users visit docs.google.com, they automatically gets the
latest version of Google Docs. Because their files are stored on Google’s
servers, they’re available from any computer. Even better, they don’t have to
worry about losing their files in a hard drive crash. (Microsoft now has its
own cloud office suite called Office 365.)
There are many other examples. Gmail and
Hotmail are cloud email services that have largely replaced desktop email clients
such as Outlook. Dropbox is a cloud computing service that automatically
synchronizes data between devices, saving people from having to carry files
around on floppy disks. Apple’s iCloud automatically copies users’ music and
other files from their desktop computer to their mobile devices, saving users
the hassle of synchronizing via a USB connection.
Cloud computing is having a big impact
for businesses too. In the 1990s, companies wanting to create a website needed
to purchase and operate their own servers. But in 2006, amazon.com launched Amazon Web
Services, which allows customers to rent servers by the hour. That has lowered
the barrier to entry for creating websites and made it much easier for sites to
quickly expand capacity as they grow more popular.
What
Is A Packet?
A packet is the basic unit of
information transmitted over the internet. Splitting information up into small,
digestible pieces allows the network’s capacity to be used more efficiently.
A packet has two parts. The header contains
information that helps the packet get to its destination, including the length
of the packet, its source and destination, and a check sum value that helps the
recipient detect if a packet was damaged in transit. After the header comes the
actual data. A packet can contain up to 64 kilobytes of data, which is roughly
20 pages of plain text.
If internet routers experience
congestion or other technical problems, they are allowed to deal with it by
simply discarding packets. It’s the sending computer’s responsibility to detect
that a packet didn’t reach its destination and send another copy. This approach
might seem counterintuitive, but it simplifies the internet’s core
infrastructure, leading to higher performance at lower cost.
What
is the World Wide Web?
The World Wide Web is a popular way to
publish information on the internet. The web was created by Timothy Berners-Lee, a computer
programmer at the European Organisation for Nuclear Research, CERN (Conseil
Européen pour la Recherche Nucléaire), in 1991. It offered a more
powerful and user-friendly interface than other internet applications. The web
supported hyperlinks, allowing users to browse from one document to another
with a single click.
Over time, the web became increasingly
sophisticated, supporting images, audio, video, and interactive content. In the
mid-1990s, companies such as Yahoo and amazon.com began building profitable businesses
based on the web. In the 2000s, full-featured web-based applications such as
Yahoo Maps and Google Docs were created.
In 1994, Berners-Lee created the World Wide Web Consortium (W3C)
to be the web’s official standards organization. He is still the W3C’s director
and continues to oversee the development of web standards. However, the web is
an open platform, and the W3C can’t compel anyone to adopt its recommendations.
In practice, the organizations with the most influence over the web are
Microsoft, Google, Apple, and Mozilla, the companies that produce the leading
web browsers. Any technologies adopted by these four become de facto web
standards.
The web has become so popular that many
people now regard it as synonymous with the internet itself. But technically,
the web is just one of many internet applications. Other applications include
email and BitTorrent.
What’s
A Web Browser?
A web browser is a computer program that
allows users to download and view websites. Web browsers are available for
desktop computers, tablets, and mobile phones.
The first widely used browser was Mosaic, created by researchers at
the University of Illinois. The Mosaic team moved to California to found Netscape, which built the first
commercially successful web browser in 1994.
Netscape’s popularity was soon eclipsed
by Microsoft’s Internet Explorer,
but an open source version of Netscape’s browser became the modern Firefox browser. Apple released its Safari browser
in 2003, and Google released a browser called Chrome in 2008. Today, Chrome is the most popular web browser with more than a third of the market.
Internet Explorer, Firefox, and Safari also have significant market share.
What
Is SSL?
SSL, short for Secure Sockets Layer, is
a family of encryption technologies that allows web users to protect the
privacy of information they transmit over the internet.
When you visit a secure website such as gmail.com,
you'll see a padlock symbol next to the URL (abbreviation for Uniform Resource
Locator – also known as web address), indicating that your communications with
the site are encrypted. Here's what that looks like in Google's Chrome browser:
That padlock symbol is supposed to
signal that third parties won't be able to read any information you send or
receive. Under the hood, SSL accomplishes that by transforming your data into a
coded message that only the recipient knows how to decipher. If a malicious
party is listening to the conversation, it will only see a seemingly random
string of characters, not the contents of your emails, Facebook posts, credit
card numbers, or other private information.
SSL was introduced by Netscape in 1994.
In recent years, there has been a trend toward major online services using
encryption by default. Today, Google, Yahoo, and Facebook all use SSL
encryption by default for their websites and online services.
When implemented correctly, SSL is
believed to be highly secure. But in 2014 a number of problems were found in
widely used SSL software. In February, a serious flaw was
discovered in Apple's implementation of SSL. The next month a flaw was found in another SSL implementation
that was popular with open source operating systems. The most serious
vulnerability, known as Heartbleed, was discovered in April. It
affects Open SSL, which is installed on a majority of the world's web servers.
What
Is The Domain Name System?
The Domain Name System (DNS) is the reason
you can access Vox by typing vox.com into
your browser rather than a hard-to-remember numeric address such as
216.146.46.10.
The system is hierarchical. For example,
the .com domain is administered by a company called Verisign. Verisign assigns
sub-domains like facebook.com, google.com and vox.com.
Owners of these second-level domains, in turn, can create sub-domains such as pages.facebook.com
as mail.google.com.
Because popular websites use domain
names to identify themselves to the public, the security of DNS has become an
increasing concern. Criminals and government spies alike have sought to
compromise DNS in order to impersonate popular websites such as facebook.com and gmail.com and intercept their private
communications. A standard called DNSSEC seeks
to beef up DNS security with encryption, but few people have adopted it.
Who
Decides What Domain Names Exist And Who Gets Them?
The domain name system is administered
by the Internet Corporation for Assigned Names and Numbers (ICANN), a non-profit organization
based in California. ICANN was founded in 1998. It was granted authority over
DNS by the US Commerce Department, though it has increasingly asserted its
independence from the US government.
There are two types of domain names. The
first is generic top-level domains (gTLDs) such as .com, .edu, .org, and .gov.
Because the internet originated in the United States, these domains tend to be
most popular there. Authority over these domains is usually delegated to
private organizations.
There are also country-code top-level
domains (ccTLDs). Each country in the world has its own 2-letter code. For
example, the ccTLD for Nigeria is .ng, the United States is .us, Great
Britain’s is .uk, and China’s is .cn. These domains are administered by
authorities in each country. Some ccTLDs, such as .tv (for the island nation of
Tuvalu) and .io (the British Indian Ocean Territory), have become popular for
use outside of their home countries.
In 2011, ICANN voted to make it easier to create new gTLDs.
As a result, there may be dozens or even hundreds of new domains in the next
few years.
Source: www.vox.com
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