INTERNETINTERNETThe Internet is a global system of interconnected computer networks that use the standard Internet protocol Suite (often called TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies.

INTRANETINTRANET Intranet is the generic term for a collection of private computer networks within an organization. An intranet uses network technologies as a tool to facilitate communication between people or work groups to improve the data sharing capability. Intranets utilize standard network hardware and software technologies like Ethernet, Wi Fi, TCP/IP, Web browsers and Web servers. An organization's intranet typically includes Internet access but is firewalled so that its computers cannot be reached directly from the outside.A common extension to intranets, called extranets, opens this firewall to provide controlled access to outsiders.

Intranet Intranet BenefitsBenefits

Increased, less expensive, environmentally friendly internal communication Low acquisition and deployment costs

Low maintenance costs

Increased information accessibility Timely, current information availability Easy information publication, distribution, and training

An extranet is a private network that uses Internet technology and the public telecommunication system to securely share part of a business's information or operations with suppliers, vendors, partners, customers, or other businesses. An extranet can be viewed as part of a company's intranet that is extended to users outside the company. An extranet requires security and privacy. These can include:1.Firewall server management2.use of digital certificates3.Encryption of messages4.the use of virtual private networks (VPNs) that tunnel through the public network.

EXTRANETEXTRANET

Uses of InternetUses of Internet1) Email: By using internet now we can communicate in a fraction of seconds with a person who is sitting in the other part of the world. Today for better communication, we can avail the facilities of e-mail. We can chat for hours with our loved ones.

2) Information: The biggest advantage that internet offering is information. The internet and the World Wide Web has made it easy for anyone to access information, and it can be of any type, as the internet is flooded with information. The internet and the World Wide Web has made it easy for anyone to access information, and it can be of any type. Any kind of information on any topic is available on the Internet.

3) Business: World trade has seen a big boom with the help of the internet, as it has become easier for buyers and sellers to communicate and also to advertise their sites. Now a days most of the people are using online classified sites to buy or sell or advertising their products or services.

4) Social Networking: Today social networking sites have become an important part of the online community. Almost all users are members use it for personal and business purposes. It is an awesome place to network with many entrepreneurs who come here to begin building their own personal and business brand.

5) Shopping: In today’s busy life most of us are interested to shop online. Now a days almost anything can be bought with the use of the internet. In countries like USA most of consumers prefer to shop from home. We have many shopping sites on internet like amazon.com, Dealsglobe.com etc.

6) Entertainment: On internet we can find all forms of entertainment from watching films to playing games online. Almost anyone can find the right kind of entertainment for themselves. When people surf the Web, there are numerous things that can be found. Music, hobbies, news and more can be found and shared on the Internet.

7) E-Commerce: E-commerce is the concept used for any type of commercial maneuvering, or business deals that involves the transfer of information across the globe via internet. It has become a phenomenon associated with any kind of shopping, almost anything. It has got a real amazing and range of products from household needs, technology to entertainment.

8) Services: Many services are now provided on the internet such as online banking, job seeking, purchasing tickets for your favorite movies, and guidance services on array of topics in the every aspect of life, and hotel reservations and bills paying. Often these services are not available off-line and can cost you more.

Hardware Requirement Hardware Requirement Minimum For Internet Minimum For Internet

ConnectionConnection Computer with browser software

Modems with communication software

800 MHz Pentium III processor

512 MB RAM 80 GB or higher Hard disk

capacity High speed internet

connection, cable

NetworkingNetworkingNetworking is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software.

Types of NetworksTypes of NetworksLANs(Local Area Networks)LANs are networks usually confined to a geographic area, such as a single building or a college campus. LANs can be small, linking as few as three computers, but often link hundreds of computers used by thousands of people.

WIDE AREA NETWORKS

(WANS)• Wide area networking

combines multiple LANs that are geographically separate. This is accomplished by connecting the different LANs using services such as dedicated leased phone lines, dial-up phone lines (both synchronous and asynchronous), satellite links, and data packet carrier services.

Network can be divided in to two main categories:Peer-to-peer.Server – based.

In peer-to-peer networking there are no dedicated servers or hierarchy among the computers. All of the computers are equal and therefore known as peers. Normally each computer serves as Client/Server and there is no one assigned to be an administrator responsible for the entire network.

Peer-to-peer networks are good choices for needs of small organizations where the users are allocated in the same general area, security is not an issue and the organization and the network will have limited growth within the foreseeable future.

The term Client/server refers to the concept of sharing the work involved in processing data between the client computer and the most powerful server computer.

Distributed NetworkingDistributed Networking is a distributed computing network system, said to be "distributed" when the computer programming and the data to be worked on are spread out over more than one computer, usually over a network.

Client-server protocolA client-server protocol is a

protocol in which there is a single server which listens for connections, usually on a specific port and one or more clients which connect to is one of three basic groups of NOS(Network Operating System). All of the it.Client-Server Protocol machines that access the server are called clients or workstations.

SECURITY ON SECURITY ON NETNET

Internet security is a branch of computer security specifically related to the Internet, often involving

browser security but also network security on a more general level as it applies to other applications or on a

whole. Its objective is to establish rules and measures to use against attacks over the Internet. The Internet

represents an insecure channel for exchanging information leading to a high risk of intrusion or fraud, such as phishing. Different methods have been used to

protect the transfer of data, including encryption.

CHITRA BENGANIROLL NUMBER-131/3B.COM (HONS)SECTION-C