2. INTRANET An intranet is a private computer network that uses Internet Protocol technologies 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.
3. Workforce productivity: Intranets can also help users to locate and view information faster and use applications relevant to their roles and responsibilities. With the help of a web browser interface, users can access data held in any database the organization wants to make available, anytime and - subject to security provisions - from anywhere within the company workstations, increasing employees' ability to perform their jobs faster, more accurately, and with confidence that they have the right information. It also helps to improve the services provided to the users. Time: Intranets allow organizations to distribute information to employees on an as-needed basis; Employees may link to relevant information at their convenience, rather than being distracted indiscriminately by electronic mail.
5. EXTRANET An extranet is a private network that uses Internet protocols, network connectivity. An extranet can be viewed as part of a company's intranet that is extended to users outside the company, usually via the Internet. 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.
7. PUBLIC NETWORK he public switched network was originally created by AT&T, who used Bell Laboratories standards to ensure that all central office switches and lines that carried calls met these preset standards. During the period 1893-1907, people needed different telephones to communicate with other on a different company’s network. The standards set by AT&T enabled everyone to communicate with anyone else regardless of the service provider since the dialing, ringing, routing and telephone numbering were all uniform.The public network consists of two services. It is important to understand the concept of switched and dedicated services since mistakes in configuring telephone networks could result in extra expense, insufficient capacity and increased maintenance.
9. Private Network In the Internet addressing architecture, a private network is a network that uses private IP address space, following the standards set by RFC 1918 and RFC 4193. These addresses are commonly used for home, office, and enterprise local area networks (LANs), when globally routable addresses are not mandatory, or are not available for the intended network applications. Private IP address spaces were originally defined in an effort to delay IPv4 address exhaustion, but they are also a feature of the next generation Internet Protocol, IPv6. These addresses are characterized as private because they are not globally delegated, meaning they are not allocated to any specific organization, and IP packets addressed by them cannot be transmitted onto the public Internet. Anyone may use these addresses without approval from a regional Internet registry (RIR). If such a private network needs to connect to the Internet, it must use either a network address translator (NAT) gateway, or a proxy server. The most common use of these addresses is in residential networks, since most Internet service providers (ISPs) only allocate a single routable IP address to each residential customer, but many homes have more than one networked device, for example, several computers and a video game console. In this situation, a NAT gateway is usually used to enable Internet connectivity to multiple hosts. Private addresses are also commonly used in corporate networks, which for security reasons, are not connected directly to the Internet. Often a proxy, SOCKS gateway, or similar devices, are used to provide restricted Internet access to network-internal users. In both cases, private addresses are often seen as enhancing security for the internal network, since it is difficult for an Internet host to connect directly to an internal system.
11. Lease Line A leased line is a service contract between a provider and a customer, whereby the provider agrees to deliver a symmetric telecommunications line connecting two locations in exchange for a monthly rent (hence the term lease). It is sometimes known as a 'Private Circuit' or 'Data Line' in the UK or as CDN (CircuitoDirettoNumerico) in Italy. Unlike traditional PSTN lines it does not have a telephone number, each side of the line being permanently connected to the other. Leased lines can be used for telephone, data or Internet services. Some are ringdown services, and some connect two PBXes. A permanent telephone connection between two points set up by a telecommunications common carrier. Typically, leased lines are used by businesses to connect geographically distant offices. Unlike dial-up connections, a leased line is always active. The fee for the connection is a fixed monthly rate. The primary factors affecting the monthly fee are distance between end points and the speed of the circuit. Because the connection doesn't carry anybody else's communications, the carrier can assure a given level of quality. An internet leased line is a premium internet connectivity product, delivered over fibre normally, which is dedicated and provides uncontended, symmetrical speeds. It is also known as an ethernet leased line, DIA line, data circuit or private circuit. For example, a T-1 channel can be leased, and provides a maximum transmission speed of 1.544 Mbps. The user can divide the connection into different lines for multiplexing data and voice communication, or use the channel for one high speed data circuit. Increasingly, leased lines are being used by companies, and even individuals, for Internet access because they afford faster data transfer rates and are cost-effective for heavy users of the Internet.
13. SMTP imple Mail Transfer Protocol (SMTP) is an Internet standard for electronic mail (e-mail) transmission across Internet Protocol (IP) networks. SMTP was first defined in RFC 821 (STD 15) (1982),[1] and last updated by RFC 5321 (2008)[2] which includes the extended SMTP (ESMTP) additions, and is the protocol in widespread use today. SMTP is specified for outgoing mail transport and uses TCPport 25. While electronic mail servers and other mail transfer agents use SMTP to send and receive mail messages, user-level client mail applications typically only use SMTP for sending messages to a mail server for relaying. For receiving messages, client applications usually use either the Post Office Protocol (POP) or the Internet Message Access Protocol (IMAP) or a proprietary system (such as Microsoft Exchange or Lotus Notes/Domino) to access their mail box accounts on a mail server.
15. POP computing, the Post Office Protocol (POP) is an application-layerInternet standardprotocol used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection. POP and IMAP (Internet Message Access Protocol) are the two most prevalent Internet standard protocols for e-mail retrieval. Virtually all modern e-mail clients and servers support both. The POP protocol has been developed through several versions, with version 3 (POP3) being the current standard. POP3 is used for most webmail services such as Gmail and Yahoo.
17. HTML HTML, which stands for HyperText Markup Language, is the predominant markup language for web pages. It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists, links, quotes and other items. It allows images and objects to be embedded and can be used to create interactive forms. It is written in the form of HTML elements consisting of "tags" surrounded by angle brackets within the web page content. It can embed scripts in languages such as JavaScript which affect the behavior of HTML webpages. HTML can also be used to include Cascading Style Sheets (CSS) to define the appearance and layout of text and other material. The W3C, maintainer of both HTML and CSS standards, encourages the use of CSS over explicit presentational markup.[1]
19. XML XML (Extensible Markup Language) is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification[4] produced by the W3C, and several other related specifications, all gratis open standards.[5] XML's design goals emphasize simplicity, generality, and usability over the Internet.[6] It is a textual data format, with strong support via Unicode for the languages of the world. Although XML's design focuses on documents, it is widely used for the representation of arbitrary data structures, for example in web services. There are many programming interfaces that software developers may use to access XML data, and several schema systems designed to aid in the definition of XML-based languages. As of 2009[update], hundreds of XML-based languages have been developed,[7] including RSS, Atom, SOAP, and XHTML. XML-based formats have become the default for most office-productivity tools, including Microsoft Office (Office Open XML), OpenOffice
