The intranet should be implemented in phased. If a network is already in place, the steps essentially revolve around selecting services and software, the operating system and special tools for content creation. The existing databases and software applications may be integrated into the intranet. This calls for a proper plan to be prepared. The important step to implementation follows.

Planning: This step includes scope of services and facilities; mail, Web sites, home pages department-wise, personnel, administration of the site, layout of pages, connecting with the internet.

Subnets: If the number of services and clients is large, there may be many subnets. IP addressing plan should be worked out in detail.

Services and software: Server hardware platforms and the software that will be used on them for hosting mail and Web services need to be finalized. For intranet users, browsers and mail clients have to be standardized. A server platform, may host both mail and Web services. As the intranet load grows, this could be split into multiple-servers. Web server, mail server, print server, Domain Name Server (DNS), workflow applications etc could be implemented on different hardware systems.

Operating system: An operating system may be chosen from the following popular server operating systems: UNIX, Linux, Windows NT, NetWare, Mac OS, OS/2, and AS/400. The choice of operating system will determine the software requirements of the Web server, mail server etc. While UNIX was the operating system on RISC systems, non-Unix platforms are equally aggressive solutions now. The OS should be installed on the server, complete with the TCP/IP suite of protocols. Web services should preferably be implemented from the very beginning. IP addresses and subnet masks should be allocated. It is better to use TCP/IP addresses duly registered with InterNIC so that connection to the Internet at a future date avoids address conflicts.

Proxy Servers: If the intranet requirements include the users connected on it to share a single Internet dial-up connection on the network, a proxy server is essential. It is the proxy server that dials into the Internet connection and all the nodes access the Internet through it.

Content Creation Software: HTML editors, Web-enabled office productivity tools are essential on client machines which are equipped with browsers and email software.

Training: The users on mail and Web applications may require training for discussion group, mailing list server, converting existing documents and reports for the intranet, and making them available to all. Skills to create new contents using the office-suites, productivity tools, HTML editors etc are also required.

Existing Databases: Set up a group of programmers to study the existing databases, and to Web-enable them for intranet.

Web Publishing: The Web is like a magazine, and content creation is like Web publishing. The magazine is on the Web server, and is used by the employees of an organization who are on the intranet. The contents should be catchy, easy to access, and up-to-date. Web design and maintenance are the major issues on an intranet.

Electronic funds transfer (EFT) systems constitute a major form of electronic commerce system in banking and retailing industries. EFT systems use a variety of information technologies to capture and process money and credit transfers between banks and businesses and their customers. For example, banking networks support letter terminals at bank offices and automated teller machines (ATM). Banks may also support pay-by-phone services allowing bank customers to use their telephones as terminals to electronically pay bills. Major forms of EFT systems are outlined below.

Banking and financial payments:

• Large-scale or wholesale payments (e.g., bank-to-bank transfer)
• Small-scale or retail payments (e.g., automated teller machines and cash dispensers)
• Home banking (e.g., bill payment)

Retailing payments:

• Credit cards (e.g., VISA, MasterCard etc.)
• Private credit/debit cards (e.g., JC Penny Card)
• Charge cards (e.g., American Express)

Online electronic commerce payments:

• Token-based payment systems
• Electronic cash (e.g., CyberCoin)
• Electronic Checks (e.g., NetCheque)
• Smart cards or debit cards (e.g., Mondex Electronic Currency Card)
• Credit card-based systems
• Encryped credit cards (e.g., SSL, CyberCash, or SET encryption)
• Third-party authorization numbers (e.g., First Virtual)

Secure Electronic Payments on the Internet:

One of the most noticeable and controversial topics in the Internet commerce today is the security of Internet transactions. While the technological difficulties may be soluble, a less obvious problem is how to define standards to let all consumers and merchants do business with each other while satisfying security requirements of the financial institutions involved. 

When a user makes an online purchase on the Internet, his credit card information is vulnerable to interception by network sniffers-software that easily recognizes credit card number formats. Several basic security measures are used to solve security problems:

• Encrypting (code and scrambling) the data passing between the customer and merchant.
• Encrypting the data passing between the customer and the company authorizing the credit card transaction
• Taking sensitive information offline.

Many companies use the Secure Socket Layer (SSL) security method developed by Netscape Communicator that automatically encrypts data passing between user Web browser and a merchant’s server. However, sensitive information is still vulnerable to misuse once it is decrypted (decoded and unscrambled) and stored on a merchant’s server. So a digital wallet approach, such as the Cyber Cash payment system, was developed. In this method one can add security software add-on modules to the Web browser. This enables user’s browser to encrypt credit card data in such a way that only the bank that authorizes credit card transactions for the merchant gets to see it.

Another security mechanism is Secure HyperText Transfer Protocol (SHTTP). To ensure a secure conversation between a Web client and a server, SHTTP works by negotiating the type to encryption scheme used between client and server. SHTTP and SSL can both be used for improved security.

To Secure Electronic Transaction, or SET, is another ordinary for electronic payment safety. In this technique, e-commerce software encrypts a digital envelope of digital certificates specifying the payment details for each operation. SET has been agreed to by VISA, Master Card, IBM, Microsoft, Netscape, and most other commerce players. Therefore, SET is expected to become the dominant standard for secure electronic payments on the Internet.

Other electronic payment systems for example, micro-payment systems like CyberCoin and DigilatCash. These technologies create currency or digital cash, sometimes called e-cash, for making payments that are very small for credit card transactions. Authentication and the encryption techniques are used to create strings of data that can be handled like currency for making cash payments. For example, Web sites like ESPNET Sports Zone, and Rocket Science Games let users chat with superstars, Discovery Online, play various kinds of video games or download the desired video segments by using digital cash micro-payment methods.

A wide area network connects computers located across a wide geographical area. For example an organization may have its offices scattered over different cities and each office needs to share data with other offices. In this case computers and LANs of different sites may be connected by public communication facility (like telephone network) or private communication network to realize a WAN. A WAN for a particular organization is called enterprise-wide network. The Internet is a popular example of WAN as it connects thousands of computers and LANs around the world.

Intermediate devices like gateways and routers and transmission facilities like telephone and data networks, fiber optic links, satellites are generally used for realizing WANs. The major features of WANs are listed below.

• Multiple computers are connected together
• Computers are spread over a wide geographic area
• A WAN usually interconnects multiple LANs
• Communication links between computers are provided by telephone networks, public data networks, satellites etc.
• Links are of low capacity (that is low data rate)
• Bit error rate is higher (1 in 100,000) compared to that for a LAN.

Bandwidth: Speed and capacity of computers and communication networks can be classified by bandwidth. The speed and capacity of data networks are generally measured in bits per second (bps). Low speed local communication channels are typically used for transmission rates from 300 to 56000 bps, but can now handle up to several Mbps for ADSL connections. They are usually TUP lines commonly used for voice communications, but are also for data communications by PCs, video terminals and fax machines. SPT lines can be used for speed up to 100 Mbps for short distances. High speed broadband digital channels allow transmission rates from 256,000 bps to several billion bps; typically they are microwave, satellite transmission and fiber optic cables.

Switching: Switching techniques used for WAN are circuit switching, message switching and packet switching. Normal telephone service relies on circuit switching. In circuit switching a switch establishes and maintains a link between a sender and receiver until the communication session is completed. In message switching, a complete message is transmitted in a block from one switching node to another.

In packet switching a message is subdivided into groups called packets. In X.25 packet switching, packets are 128 characters long, while they are of variable length in frame relay packet switching. Frame Relay is considerably faster than X.25 and is used by many large companies for their wide area networks. ATM (Asynchronous transfer mode) is a fast emerging high speed cell switching network technology. An ATM system, using BISDN (Broadband Integrated Service Digital Network), organizes voice, video, and other data into fixed cells of 53 bytes and send them to their next destination. ATM networks are becoming popular for the faster high-capacity multimedia services for voice, video and other high speed applications. Currently available network technology with data rates for WAN are listed below.

Network Technologies	Typical Data Rate
DDN: Digital Data Network	2.4 kbps - 2 Mbps
PSN: Packet Switching Network	2.4 kbps - 64 kbps
Frame Relay Network	56/64 kbps - 2 Mbps
ISDN: Integrated Services Digital Network	64/128 kbps - 2Mbps
ATM: Asychronous Transfer Mode	25/155 Mbps - 2.4 Gbps

The computer organizing a transaction must identify its intended destination with a unique address. Every computer on the Internet has a 4-part numeric address, called the IP (Internet Protocol) address. The IP address contains routing information that identifies destination location. Each of the four parts is a number between 0 and 255, so an IP address looks like this: 108.64.125.116.

Computers have no trouble working with such numbers, but humans are not so skilled. Therefore, computers connected to the Internet use an address system called a Domain Name System (DNS), where and address uses words instead of numbers.

DNS address have two parts: an user name, followed by a domain that identifies the type of institution that uses the address, such as .com for commercial or .edu for schools, colleges, and universities. Microsoft’s DNS address is Microsoft.com and Google’s DNS address is google.com. Within the United States, the last three letters of the domain usually tell the types of institution. The following table lists the most common types.

Domains	Types of organization
.com	(Business) Commercial
.edu	Educatonal
.gov	US Government
.mil	US Military
.net	Gateway or host
.org	Other organization

Large institutions and big corporations may divide their domain address into smaller sub-domains. A business with many branches might have a sub-domain for each office. Sub-domains may be broken into even smaller sub-domains, like: du.bangla.net. Outside the United States, domains usually identify the county in which the system is located, such as .in for India, .jp for Japan, .ca for Canada or .fr for France. A geographic domain address may include a sub-domain. An example could be: www.telemagazine.ac.uk.

DNS and IP address identify individual computers. A single computer might have many users, each of whom must have an account. Some of the largest domains may have huge number of different user names. When a message is sent to a person that person’s user name is the address identifies the recipient. The standard format is: the user name first, “at” symbol @, and finally the DNS address. Therefore, Imran’s e-mail address might be: Imran@titas.com.

Electronic-mail:

The most common use of the Internet is for the e-mail. Anyone with an e-mail account can send messages to other users of the Internet. Most e-mail programs also permit users to attach data files and program files to messages. E-mail is not a live connection between the sender of a message and its recipient. There is always a delay between the sending time of a message and its arrival time at the distention. Sometimes that delay is just a few seconds, but it is always there.

When a message is sent the computer presses it to a post office server, which identifies the destination address and passes it through the Internet to a mail server, where the message is stored in a mailbox until the recipient looks for it. The sender computer creates the message and sends it to a local post office server. The post office server passes the message through the Internet to the recipient’s mail server which passes it to the recipient’s computer. E-mail programs generally combine the following features.

• A text editor for writing and editing messages.
• Arrangements for storing names and e-mail addresses.
• Ability to send messages to a post office server.
• Ability to get messages from a mail server.
• A manager that organizes and stores the sent and received messages.

There is an e-mail program included in Windows 98 and many others are available separately. One of the most popular e-mail programs is Eudora, which exists in versions for both Windows and Macintosh operating systems. Besides one-to-one, Internet e-mail is also used for one-to-many, in which the same message goes to a list of names.

The World Wide Web (the Web or WWW) was created in 1989 at the European Particle Physics Laboratory in Geneva, Switzerland. Originally it was created as a method for incorporating footnotes, figures, and cross-references into online hypertext documents in which a reader can click on a word or phrase in a document, and immediately jump to another file. The second file may be located on the same computer or anywhere else on the internet. The WWW organizes widely scattered resources into a seamless whole.

The Web browsers have changed the way people use the Internet. Web pages are now used to distribute news, interactive educational services, product information and catalogs, highways traffic reports, live audio and video, among many other things. Interactive Web pages permit users to consult databases, order products and information, and submit payment with a credit card or other account number.

The latest Web browsers, including Google Chrome, Mozilla Firefox, Netscape Navigator and Microsoft’s Internet Explorer, can open file viewers and other application programs automatically when they receive graphic images, audio, video, and other files. Users also can import live, interactive data (such as financial information that changes frequently) and executable programs from the World Wide Web.

The organization of the World Wide Web is built on a set of rules called HyperText Transfer Protocol (HTTP) and a page description language called HyperText Markup Language (HTML). HTTP uses Internet addresses in a special format called a Uniform Resource Locator, or URL. The format or URLs is: type: //address/path

Here type specifies the type of server in which the file is located. The address part is the address of the server, and finally the path is the location within the file structure of the server. As an example the URL for the IEEE membership renewal is: http://www.ieee.org/renewal

A document that uses HTTP is known as a Web page. A Web page contains information about a particular subject with links to related Web pages. Many Web sites contain a top-level home page that has pointers to additional pages with more information. For example, a university might have a home page with links to a campus guide, Telnet access to the library, and separate pages for individual departments and offices.

Thousand of new Web pages appear every day, but they are not always easy to find. The World Wide Web does not provide a basic structure for locating resources. To fill this gap, search tools are available online. One of them is Google, Whose URL is https://www.google.com. Google is an extensively directory with menu that lists millions of web sites, organized by topic and a search engine that looks for specified words in titles and addresses of the Web sites in the directories. Other popular search tools include InfoSeek, Lycos, Magellan, and Excite, to name a few.