INTERNET
The Internet is a network that is available to anyone with an
Internet-connected device. It is a massive collection of networks
sharing information publicly in the form of interlinked Web pages.
Internet Protocol defines a site's unique location which most users
see as a domain name or URL. The network is literally world-wide
and is often referred to as the world wide web.
INTRANET
An intranet network is only available to a small group of
people. Intranets are mainly used within businesses and
organizations to provide access to files and applications among
networked computers and servers. Intranets may or may not have
access to the Internet. If an intranet does connect to the
Internet, a firewall is used to prevent outside access to the
intranet. The purpose is to allow people within the same company to
share information over a local area network. It is sometimes
referred to as a private Internet.
EXTRANET
An extranet is similar to an intranet, but is accessible via a
Web portal. An extranet may be accessed from anywhere if the user
has a valid user name and password. The purpose of this type of
network is to allow collaboration and sharing of resources not only
in-house but with a select group of outside users. For instance,
businesses will use an extranet to allow customers to log in to
provide input on projects. Another example is using aVIRTUAL
PRIVATE NETWORKto allow employees to log in to the network when
they're are not in the office.
MAIN DIFFERENCES
The main difference between the three is accessibility. The
Internet is public while the other two are highly restricted. Home
users, if they use one at all, would only use an intranet to share
files between computers and typically use the Internet when
searching for and sharing information. Businesses and organizations
are the main users of both intranets and extranets in order to
restrict access to confidential data.
Internet vs Intranet vs Extranet
Computer networks differ from each other depending on their
topology. Each type of network has its own characteristics which
provide desired level of service to the audience. There are three
comprehensive types of networks, Internet, Intranet and extranet.
Each network shares same communication technologies. They differ in
terms of size, access levels and the nature of users.
Internet
Internet is a Public network with thousands of computers
(servers and clients) interconnected to share information. Clusters
of computer networks are interconnected to build the network
spanning all over the world. There is no centralized controller to
control communication. It relies on network devices and protocols
(Ex routing protocols) previously agreed upon. Any user can access
Internet through an Internet Service Provider (ISP). Generally,
internet is unregulated and uncensored, but there are some
countries with restrictions imposed on internet access to their
citizen. Although there is no centralized entity to control, ICANN
(The Internet Corporation for Assigned names and Numbers) manages
Internet Protocol Addresses and Domain Names.
Intranet
Intranet is a Private network with a limited number of computers
interconnected and controlled in a defined manner. Intranet is
setup and controlled by an organization, to ensure secure and
uninterrupted connection between members to exchange information
more efficiently. Organization requirements may include sharing
latest news updates, management information, organization changes,
new policies and procedures etc.
Intranet is much like the Internet, but it is isolated from the
external world. Firewalls are used to connect Intranet to the
outside world when it has to be connected to Internet. It uses same
protocols like TCP/IP. Size of the Intranet depends on the
organization requirements. It may span over one building, one area,
or one country. In addition, there are many multinational
organizations maintain Intranets between countries using dedicated
fiber optic connections. Communication efficiency between network
devices is high since the bandwidth is fully assigned to a fixed
number of users. There are no frequent traffic spikes, channel
breakdowns or server offline situations in the Intranet. Intranet
may be accessible through the Internet. There are techniques like
VPN connection to provide secure connections in such
situations.
Extranet
Extranet is part of an Intranet, which is also categorized as a
Private Network. It is controlled and managed by an organization,
to provide secure access to Intranet from the outside world. Many
business organizations need their business partners and customers
to connect to Intranet to enhance communication and efficiency.
Since the Intranet permits only internal members to gain access,
external members (partners and customers) use Extranet to access
the network. System administration/management can decide which
users should allow through Extranet. Generally, external users are
given limited access over the Intranet.
Not only external users, sometimes members of the organization
itself who may need to access the network over the Internet can use
Extranet.
What is the difference between Internet, Intranet and
Extranet?
When it comes to size of the network, Internet is the largest
and consists hundreds of thousands of network devices and
interconnections. Intranet size may span from hundreds to several
thousands of computers. Extranet comes as a part of Intranet, so it
is the smallest.
Internet is a public network. Intranet and Extranet are private
networks.
Users can access Internet anonymously. Users should have valid
username/password to access Intranet and Extranet.
Generally, Internet is unregulated and uncensored. But
Intranet/Extranet is regulated by the organization policies.
In the nature of users, Internet has unlimited number of
anonymous users. Intranet keeps limited number of predefined users
who are internal members of the organization. Extranet users are
mostly non-organizational users.
What is the difference between extranet and intranet?An extranet
has a portal to the outside world, while an intranet is an entirely
internal network. Both intranet and extranet technology operates
with normal HTML functionality, including proprietary
limited-access Web sites, e-mail and FTP capabilities. Intranets
and extranets typically look like regular Web sites, but they can
only be accessed by a specific user group; either entirely
internal, or with restricted access for some external users.
Extranets still aren't open connections, though; extranet users
require a logon and security certificate to access extranet
functionality. Intranets and extranets by definition have different
levels of security, and thus each technology is better suited to
different types of applications.
The differences in technology affect security.By the very nature
of the two technologies, intranet and extranet solutions are not
equally secure. Intranet technology is completely secure, because
it is entirely internal. Intranets are hosted on local area
connections, or restricted behind a firewall. Intranets have no
portals to the outside world, or they're no longer intranets; they
become an extranet with an external portal. A given organization
could have a series of both intranets and extranets to serve
company needs.
Because extranet technology involves a portal beyond company
resources, the extranet by definition is less secure. Advances in
Internet security and encryption mean that extranets are still
extremely secure; some sources estimate that extranet encryption
could take hackers years to crack. However, the vulnerability is
there, and that makes an extranet unsuitable for some
applications.
Extranet technology serves a different purpose in business
applications.Because extranet technology is less secure by nature,
it tends to serve a different purpose in business applications from
a network intranet. An extranet is typically used in
business-to-business communications, giving business clients a
convenient HTML-based point of contact.
Extranets can enable business clients to place orders, check
supply inventories, peruse order histories, browse FAQs or help
documents or perform other company-related interactions. Intranets
are used more to exchange proprietary internal information in a
secure setting, such as managing payroll, distributing human
resources documentation or sharing data and collaborating within
the company.
Who uses an intranet, and who uses an extranet?By definition, an
intranet is restricted to users within a company, as an intranet
has no external portals. Therefore, intranet users might include an
executive team, accounting department, human resources department
and even regular company employees. Depending on how an intranet is
configured, different users might have access to different levels
of information.
A company extranet, on the other hand, is designed as a way for
a company to share data with external users. A company extranet may
extend to vendors, suppliers, business clients and customers: The
possibilities are limited only by the scope of the extranet. Each
of these users requires a unique logon and security certificate,
and extranet administrators can typically track extranet use
through the security certificates.