For further information on Intranet and Extranet, the following power point presentation can be referred to.


https://docs.google.com/present/edit?id=0AcYgbWVenRlmZGRmcTQ4ODhfMGYzNHFiaGcz&hl=en_US

For further information on Intranet and Extranet, the following word document can be referred.

https://docs.google.com/document/d/1e5uKn7koXjvdGV5-0MYoY1vUbANJcUG8luk6p_EVffI/edit?hl=en_US

Intranet vs Extranet

An extranet can be understood as an intranet mapped onto the public Internet or some other transmission system not accessible to the general public, but managed by more than one company's administrator(s). For example, military networks of different security levels may map onto a common military radio transmission system that never connects to the Internet. Any private network mapped onto a public one is a virtual private network (VPN), often using special security protocols.

For decades, institutions have been interconnecting to each other to create private networks for sharing information. One of the differences that characterize an extranet, however, is that its interconnections are over a shared network rather than through dedicated physical lines. With respect to Internet Protocol networks, RFC 4364 states "If all the sites in a VPN are owned by the same enterprise, the VPN is a corporate intranet. If the various sites in a VPN are owned by different enterprises, the VPN is an extranet. A site can be in more than one VPN; e.g., in an intranet and several extranets. We regard both intranets and extranets as VPNs. In general, when we use the term VPN we will not be distinguishing between intranets and extranets. Even if this argument is valid, the term "extranet" is still applied and can be used to eliminate the use of the above description."

Intranet diagram

An intranet is a computer network that uses Internet Protocol technology to securely share any part of an organization's information or network operating system within that organization. The term is used in contrast to internet, a network between organizations, and instead refers to a network within an organization. Sometimes the term refers only to the organization's internal website, but may be a more extensive part of the organization's information technology infrastructure. It may host multiple private websites and constitute an important component and focal point of internal communication and collaboration. Any of the well known Internet protocols may be found in an intranet, such as HTTP (web services), SMTP (e-mail), and FTP (file transfer protocol). Internet technologies are often deployed to provide modern interfaces to legacy information systems hosting corporate data.

Extranet diagram

extranet

An extranet is a computer network that allows controlled access from the outside, for specific business or educational purposes. An extranet can be viewed as an extension of a company's intranet that is extended to users outside the company, usually partners, vendors, and suppliers. It has also been described as a "state of mind" in which the Internet is perceived as a way to do business with a selected set of other companies (business-to-business, B2B), in isolation from all other Internet users. In contrast, business-to-consumer (B2C) models involve known servers of one or more companies, communicating with previously unknown consumer users. An extranet is like a DMZ in that it provides access to needed services for channel partners, without granting access to an organization's entire network.