prof max class notes updated15jul2010

AnswerstotheQuestionBank2010PARTTIMEMBA|2YEAR 1ST SEMESTERINTRODUCTIONTOCOMPUTERS|MIS

Prof.MaxWilliamDCosta|[email protected]|(m)9821439790[CompiledonJuly15,2010]

MET Part Time MBA Answers to Questions in the Question Bank (Class Notes 2010)

-- Author: Prof. Max William DCosta ([email protected])

Compiled on: July 15, 2010 by Prof. Max DCosta @ MET SOM Page 2 of 138

Q1 Q2 Q3 Q4 Q87

Using specific examples, describe how computerization would help your department perform more efficiently and effectively. Also explain how computerization will help better decision-making, analysis and planning? In what ways will the use of IT and Internet enhance your job function as a Middle Manager? Discuss with examples with respect to either HRD Function or Marketing Function or Finance Function? Giving suitable examples explain how and why IT and computers have contributed in increasing productivity and competitiveness of organizations in doing business. Write a note on how IT can help an organization in gaining competitive advantage How does IT contribute towards increasing productivity and in doing business better? Explain with reference to any one function in your organization in detail.

(Ans 1-4, 87) Scenario before IT:

More paper work Lack of storage space Communication was expensive and huge Telephone bills were incurred Redundancy of information Lack of Information security

Scenario after IT:

Less paper work due to the use of computerized transactions Storage space greatly increased to store huge amounts of data running into terabytes Streamlined communication and convergence has enabled different modes of

communication as well as different devices to communicate and share information across the globe

Communications today is less expensive and in most cases almost free as many calls happen online using free softwares like Skype and other online chat and messenger applications.

Use of databases have helped optimize data and reduce redundancy thereby offering easy and powerful access to the information warehouses and showing different users the data they seek in different ways wherever and whenever they need it.

Uses of sophisticated databases have also brought in data security leading to overall information security and safety. This allows for only authorized users to communicate and access data from the databases

Data Analysis and generation of Metrics have helped users and organizations perform their decision making activities to be more effective and accurate.

Information has now become more Accessible, Reachable, Portable and Editable across mediums and devices and across users as well.




IT and Internet has enhanced the job functions of a middle managers working in the HR, Finance and Marketing functions in the following manner: HRD Function

Recruitment processes have been automated wherein software tools like CV scanners and ATS (Applicant Tracking Systems) have been introduced to scan and filter the appropriate CVs from thousand applicants and then tracking the applicants candidature from recruitment to selection in the organization.

Payroll function also uses IT to automate disbursement of salaries and claims and other financial related transactions that concern the employees or the organization and its stakeholders

Online banking ensures that organizations can deposit employee salaries in banks and employees can transact online without having to physically visit a bank or deal in physical cash.

Use of E-HRIS (Electronic Human Resource Information Systems) has automated the tasks of employee HR communication. They serve as a virtual HR manager who takes care of employee related transactions online. These transactions can range from entering daily times sheets, claiming for late sitting re-imbursements, Mediclaims and LTA claims, posting grievances online to applying for leave online etc.

Allocations of employees and online skill matrices of employees with their skill sets helps the HR functions to optimally use the human capital

Use of Intranets have empowered the HR managers to leverage this platform for Internal communication within the organization

Today Employee Satisfaction and other key surveys are conducted online using the companies Intranets and the data collected is collated, analyzed and used for decision making by the HR function.

Use of Enterprise HR applications like SAP, Oracle PeopleSoft etc have enabled the HR functions to work well with the human capital across business functions, branches and continents in a very synchronous and effective manner

Finance Function

Use of softwares like Tally and other financial accounting packages have helped the finance departments and financial accountants greatly by automating financial transactions and ensuring their accuracy and integrity

Today balance sheets and other financial records can be easily created, maintained and distributed online to stakeholders

Online banking has enabled transactions between financial departments and banks Usage of financial modules of Enterprise Resource Planning applications have

empowered organizations to effectively manage their finances Automated tools help Finance managers make projections and predictions thereby

guiding the overall organization goals E-Finance has reduced paperwork and created a revolution where digital money /

transactions have greatly impacted global electronic commerce and global transactions Marketing Function

Today Marketing managers use tools like e-Marketing to reach out to customers across the globe.

Marketing has leveraged the power of IT and internet in bringing together new markets and new customers and has created a virtual marketplace where users, organizations exchange goods, services, information, ideas etc.




Customers can now give their product related suggestions, feedbacks and even register their issues or complaints to the manufacturing or product development departments directly using CRM (Customer Relationship Mgmt) software's.

Middle to high level managers can use the internet and the various communication facilities that come with it to network with their user base.

Online banner advertisements can rake in a lot of money and generate new revenue streams.

Traditional brick and mortar business is now being complimented and eventually replaced by online business and e-Commerce.

Enterprise Resource Planning Applications like SAP, Oracle etc have modules for Marketing and Distribution that helps the materials planning function, logistics, Supply Chain functions and CRM functions as well.

Marketing managers can now IT enable the small and third party vendors to connect to their organizations network so that they can check the organizations inventory levels and continuously replenish them as and when required, this helps them to save a lot as they do not have to store goods unnecessarily thereby incurring warehousing expenses. Instead they can operate on Just in Time basis.

Marketing Services in the services industry can also be greatly enhanced by use of IT and internet as now all services can be accessed online, and users can get help online as well as offline.

This is how computerization, the advent of IT and Internet has helped departments like these to perform more efficiently and enhanced the role of middle level managers in organizations.




Q5 Write a note on Operating Systems Q6

What are the purposes of the Operating System? Explain the functions of the Operating System?

Q7 Explain the functions of the Operating System? Q8 Enumerate the key purpose and name one example of the Operating System? (Ans 5-8)

Definition of an Operating System: An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. It is a systems software that manages the operations of a computer. Without it you cannot start a computer. It is the most important program that runs on a computer. Every general-purpose computer must have an operating system to run other programs. Operating systems perform basic tasks, such as recognizing input from the keyboard, sending output to the display screen, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers. For large systems, the operating system has even greater responsibilities and powers. It is like a traffic cop -- it makes sure those different programs and users running at the same time do not interfere with each other. The operating system is also responsible for security, ensuring that unauthorized users do not access the system. Most operating systems come with an application that provides an interface to the OS managed resources. These applications have had command line interpreters (e.g. DOS Disk Operating System) as a basic user interface but, since the mid-1980s; have been implemented as a graphical user interface (GUI) for ease of operation. Operating Systems themselves have no user interfaces; the user of an OS is an application, not a person. The operating system forms a platform for other system software and for application software. Windows, Linux, and Mac OS are some of the most popular Operating Systems.




Types of Operating Systems

a) Single User Operating System b) Multi-User Operating System

Single User Operating System

This OS is used for standalone PCs (e.g. MS DOS) OS/2 and Win NT are also single user, multi tasking OS for micro computers Most Personal Computers and Workstations are Single User computer systems that have

a single user OS

Multi-User Operating System

This OS is used for those computers having many terminals connected to it. E.g. Linux, Novell Netware, Unix

All Mainframes and Minicomputers are multi-user systems that run on a multi-user OS Operating System Techniques

Multiprogramming - In which a single CPU works on two or more programs - In this technique the OS keeps the CPU busy by allowing either batch

multiprogramming or timesharing multiprogramming

Multiprocessing - Refers to a computers ability to support more than one process (program) at the

same time. - It is also referred to as parallel processing - Unix is one of the most widely used multiprocessing systems

Multitasking

- It is the computers ability to execute more than one task at the same time. - In multitasking only one CPU is involved, but it switches from one program to

another so quickly that it gives the appearance of executing all of the programs at the same time.

Multithreading

- Its the ability of an OS to execute different parts of a program, called threads, simultaneously.

- Programmers must carefully design the programs in such a way that all the threads can run at the same time without interfering with each other.

Real Time

- It means occurring immediately. - Real time operating systems are systems that respond to input immediately. - They are useful for tasks like GPS, Navigation in which computers are required

to react to a steady flow of new information without interruption or delays. Functions of an Operating System




a) Process Management - OS helps the CPU allocate resources for executing programs / processes. A process is a program in execution. E.g. Spooling, printing etc. The Operating System helps in the creation, deletion, suspension, resumption and synchronization of processes.

b) Memory Management

- Memory is a large array of words and bytes each with its own address. The CPU reads from and writes to memory. The OS keeps track of currently used memory and who is using it. It decides which processes to load in memory when memory space becomes available and it allocates & de-allocates memory space as needed.

c) Storage Management

- The OS deals with the allocation and reclamation of storage space when a process / program is opened or terminated. The OS helps in reading of data from the disk to the main memory (RAM) in order to execute processes.

d) I/O (Input / Output) System

- The OS helps the I/O devices to communicate easily as it hides the peculiarities and device driver details from the end user.

e) File Management

- The OS provides a logical view of Information Storage, it maps files on physical devices. It helps in the creation, deletion of files and directories, manipulating of files and directories on to the storage and also does a backup. It offers a very user friendly interface like the windows explorer for end users like us to work with files easily.

f) Protection System

- The OS protects processes from interference of other processes and it checks for authorization of processes and allows them to access CPU resources.

g) Networking

- Distributed computing systems require Multi-user OS for allowing processes and users the access to shared resources on the network.

h) System and Resource Monitoring - The OS helps monitor resource usage and provides information on system performance.




Q9

Explain the importance of Documentation / System Documentation.

(Ans 9) Definition of Documentation: Documentation can be described as the information for Historical, Operational and Reference purposes. Documents establish and declare the performance criteria of a system. Documentation explains the system and helps the people understand and interact with the system. Types of Documentation:

a) Program Documentation: This begins in the system analysis phase and continues during systems implementation. It includes process descriptions and report layouts. Programmers provide documentation with comments that make it easier to understand and maintain the program. A system analyst must verify that the program documentation is accurate and complete.

b) System Documentation: It describes the systems functions and how they are implemented. Most systems documentation is prepared during the system analysis and system design phases. Documentation consists of:

- Data Dictionary Entries - Data Flow Diagrams - Object Models - Screen Layouts - Source Documents - Initial Systems Request

c) Operations Documentation:

Typically used in a minicomputer or a mainframe environment with centralized processing and batch job scheduling. Such documentation tells the IT Operations group how and when to run programs. A Common example is a program run sheet which contains information needed for processing and distributing output.

d) User Documentation: A User Documentation includes the following items, namely:

- A complete System Overview - Source document description with samples - Menu and data entry screens - Reports that are available with samples - Security and Audit trail information - Responsibility for Input / Output and Processing - Procedure for handling bugs, changes and problems - Examples of exceptions and error situations - Frequently Asked Questions (FAQs)




- Explanation of Help and Updating the Manual - Online documentation to empower users and reduce the need for direct IT

support - Global and Contextual Help - Interactive Tutorials - Hints and Tips - Hypertext and Interactive Tutorials




Q10 What is a Graphical User Interface (GUI)? Q11 Differentiate between Graphical User Interface and Character User Interface? (Ans 10-11) GUI (Graphical User Interface) Abbreviated GUI (pronounced GOO-ee). A program interface that takes advantage of the computer's graphics capabilities to make the program easier to use. Well-designed graphical user interfaces can free the user from learning complex command languages. Graphical user interfaces, such as Microsoft Windows and the one used by the Apple Macintosh, feature the following basic components:

pointer: A symbol that appears on the display screen and that you move to select objects and commands. Usually, the pointer appears as a small angled arrow. Text -processing applications, however, use an I-beam pointer that is shaped like a capital I.

pointing device: A device, such as a mouse or trackball, that enables you to select objects on the display screen.

icons: Small pictures that represent commands, files, or windows. By moving the pointer to the icon and pressing a mouse button, you can execute a command or convert the icon into a window. You can also move the icons around the display screen as if they were real objects on your desk.

desktop: The area on the display screen where icons are grouped is often referred to as the desktop because the icons are intended to represent real objects on a real desktop.

windows: You can divide the screen into different areas. In each window, you can run a different program or display a different file. You can move windows around the display screen, and change their shape and size at will.

menus: Most graphical user interfaces let you execute commands by selecting a choice from a menu.

The first graphical user interface was designed by Xerox Corporation's Palo Alto Research Center in the 1970s, but it was not until the 1980s and the emergence of the Apple Macintosh that graphical user interfaces became popular. One reason for their slow acceptance was the fact that they require considerable CPU power and a high-quality monitor, which until recently were prohibitively expensive. In addition to their visual components, graphical user interfaces also make it easier to move data from one application to another. A true GUI includes standard formats for representing text and graphics. Because the formats are well-defined, different programs that run under a common GUI can share data. This makes it possible, for example, to copy a graph created by a spreadsheet program into a document created by a word processor. Many DOS programs include some features of GUIs, such as menus, but are not graphics based. Such interfaces are sometimes called graphical character-based user interfaces to distinguish them from true GUIs. CUI (Character User Interface) Describes programs capable of displaying only ASCII (American Standard Code for Information Interchange) characters. Character-based programs treat a display screen as an array of boxes, each of which can hold one character. When in text mode, for example, PC screens are typically divided into 25 rows and 80 columns. In contrast, graphics-based programs treat the display




screen as an array of millions of pixels. Characters and other objects are formed by illuminating patterns of pixels. Because the IBM extended ASCII character set includes shapes for drawing pictures, character-based programs are capable of simulating some graphics objects. For example, character-based programs can display windows and menus, bar charts, and other shapes that consist primarily of straight lines. However, they cannot represent more complicated objects that contain curves. A Command Line Interface or CLI is a method of interacting with an operating system or software using a command line interpreter. A command line interpreter is a computer program that reads lines of text entered by a user and interprets them in the context of a given operating system or programming language. This requires the user to know the names of the commands and their parameters, and the syntax of the language that is interpreted. From the 1960s onwards, user interaction with computers was primarily by means of command line interfaces Distinguish between GUI & CUI / CLI Graphical User Interface (GUI)

Character User Interface (CUI)

Generally used in Multimedia, eLearning, Demos etc

Generally used in programming languages

Consists of a Visual / Graphical control features using toolbars, buttons, icons, menus etc

Consists of character control features such as text elements or characters

Used to create animations or pictures Used to create words or sentences or syntax commands

A variety of input devices are used to manipulate text & images as visually displayed

Allows users to specify options through function keys

Its usually a graphical Interface, e.g. Web pages, Navigation etc

Its purely textual (commands which are understood by computers)

GUI can be affected by Virus Proves less affected by virus E.g. Windows OS, Apple OS E.g. Disk Operating System (DOS)

All Operating Systems today provide a Graphical User Interface. Applications use GUI, e.g. Web Applications, ATM Softwares etc. The GUI uses metaphors for helping users understand the nature of activities they can perform. E.g. Home Icon which indicates the homepage, Lock and Key Icon which indicates security etc. GUI may also include audio, video. GUI is also known as Look and Feel. Apple Mac OS & Win OS are todays familiar GUIs.




Q12 What is Internet? Q16 Why Internet is called the Network of Networks? How does it work? (Ans 12, 16) The Birth of the Internet While computers were not a new concept in the 1950s there were relatively few computers in existence and the field of computer science was still in its infancy. Most of the advances in technology at the time cryptography, radar, and battlefield communications were due to military operations during World War II, and it was in fact, government activities that led to the development of the Internet. On October 4, 1957, the Soviets launched Sputnik, the first unmanned satellite in space, and the US Government under President Eisenhower subsequently launched an aggressive military campaign to compete and surpass the Soviet activities. From the launch of Sputnik and the U.S.S.R. testing its first ICBM (Intercontinental Ballistic Missile) the Advanced Research Projects Agency (ARPA) was born. ARPA was the U.S. Governments research agency for all space and strategic missile research. In 1958, NASA was formed, and the activities of ARPA moved away from aeronautics and focused mainly on computer science and information processing. One of ARPAs goals was to connect mainframe computers at different universities around the country so that they would be able to communicate using a common language and a common protocol. Thus the ARPAnet The worlds first multiple-site computer networkwas created in 1969. The original ARPAnet eventually grew into the Internet. The Internet was based on the concept that there would be multiple independent networks that began with the ARPAnet as the pioneering packet-switching network but would soon include packet satellite networks and ground-based radio networks. Why the Internet is also known as the network of networks The internet is the publicly accessible worldwide system of interconnected computer networks that transmit data by packet switching using a standardized Internet Protocol like TCP/IP (i.e. Transmission Control Protocol / Internet Protocol) and may other protocols. It is made up of thousands of smaller commercial, academic, domestic and government networks. It carries various information and services, such as electronic mail, online chat and the interlinked web pages and other documents of the World Wide Web. Unlike online services, which are centrally controlled, the Intranet is decentralized by design. Each Internet Computer, called a host, is independent. Its operators can choose which Internet services to use and which local services to make available to the global internet community. It is possible to gain access to the Internet through a commercial ISP (Internet Service Provider).




Illustration of the Internet Architecture:

Difference between Internet and the World Wide Web Many people use the terms Internet and World Wide Web interchangeably, but in fact the two terms are not the same thing. They are both separate but related concepts. The Internet is a massive network of networks. It connects millions of computers together globally, forming a network in which any computer can communicate with any other computer as long as they are both connected to the Internet. Information that travels over the Internet does so via a variety of languages known as protocols. The World Wide Web also known as the Web is a way of accessing information over the medium of the Internet. It is an information-sharing model that is built on top of the Internet. The web uses the HTTP Protocol. Web services which use HTTP to allow applications to communicate in order to exchange business logic use the World Wide Web to share information. The web also makes use of browsers such as Internet Explorer or Netscape, or Firefox to access web documents called web pages that are linked to each other via hyperlinks. Web documents contain graphics, sounds, text and video. So the Web is just a large portion of the Internet but the two terms are not the same and should not be confused with each other.




Q13 Internet Technology and Electronic Commerce has brought the manufacturers and

customers very close to each other. This should result into better Customer Relationship Management and Supply Chain Management. Please explain.

Q29 Internet and E-Commerce has brought the manufacturers and consumers very close to each other, resulting in better Customer Relation Management and Supply Chain Management? Please explain?

(Ans 13, 29) Internet has paved the way for Electronic Commerce (e-Commerce), which can be defined as the business activities conducted using electronic data transmission technologies, such as those used on the Internet and the World Wide Web. It involves buying, selling, transferring or exchanging products, services, and / or information via computer networks and is a major distribution channel for goods, services and managerial and professional jobs. Companies today are interested in E-Commerce simply because it can help increase sales and profits and decrease costs. Even a small firm that advertises on the web can get their message out to potential customers in every country in the world. E-Commerce has proven to have many benefits and advantages. E-Commerce plays a major role in global reach. It expands the marketplace to national and international markets. E-Commerce allows firms to now reach narrow market segments that are geographically scattered. People in third world countries are now able to enjoy products and services that were unavailable in the past. It is important to understand that not only does E-Commerce benefit the Seller or the Company, but it also benefits the buyer or the customer. One main benefit of E-Commerce is that it is particularly useful in creating virtual communities that become ideal target markets for specific types of products and services. Just as E-Commerce increases the sales opportunities for the seller, it increases the purchasing opportunities for the buyer. With minimum investment, a business can use E-Commerce to easily and quickly identify the best suppliers, more customers and the most suitable business partners worldwide. By expanding the base of consumers and suppliers, enables an organization to buy at cheap rates and sell more at competitive and lower prices. E-Commerce has also given a great boost to Supply Chain Management (SCM). Today using E-Commerce companies can manage the integration of all activities within and between enterprises. Some of these activities include Procurement, Inventory Management and Logistics. The Internet and E-Commerce revolution allows you to manage your Supply Chain better by effectively integrating a system of suppliers, partners, customers and employees. This nowadays is done online with the help of customized Extranets, use of Virtual Private Networks, Emails and other collaboration tools and hence today this activity can be referred to as e-SCM. The Internet and E-Commerce has benefited the SCM process by decreasing operating costs through reduced inventory requirements. It has improved customer satisfaction by maintaining adequate inventory and has improved productivity and logistics. The Internet will help you provide better customer service by delivering rich on-demand solutions. Better customer service results in brand loyalty and this results in good revenue. Internet and E-Commerce has helped companies support their existing customers, develop new customers and retain profitable customers. Today customers can reach the manufacturers online and share market research data; they can make complaints online and even send their suggestions for product / service improvements online and even track the progress of their orders online (e.g. FedEx allows its customers to track the status of their courier packages online.) Thus it can be said that the use of Internet and E-Commerce has improved margins, increased customer awareness and increased competitive advantage in todays new economy and has




brought the manufacturers and customers closer to each other and has resulted into better CRM and SCM. Q17 Q18 Q53

Explain Protocols in Communication? Define and explain a protocol. What is a Protocol?

(Ans 17, 18, 53) Protocols are a collection of rules and procedures that control the transmission of data between devices. They enable intelligent exchange of data between incompatible devices. Protocols are needed to minimize transmission errors. They are as set of rules for sending and receiving electronic messages. Protocols split data files into small blocks or packets in order to transfer them over a network. Protocols use algorithms to measure data packets to ensure their proper receipt.

Transport protocols provide end-to-end data exchanges where the network devices maintain a connection or session. Network protocols handle addressing and routing information, error control and requests for transmissions. These protocols function at the transport & network layers of the OSI reference model) TCP/IP Protocol was initially designed to provide a method for interconnecting different packet switching networks in the ARPANET which was the foundation of the Internet. TCP is a connection-oriented transport layer protocol that uses the connectionless services for IP to




ensure reliable delivery of data. TCP was introduced with UNIX and used in the IBM environment and it provided file transfer, email and remote logon across large distributed client server systems. WAP (Wireless Access Protocol) WAP utilizes the wireless transmission protocols to transfer content from the internet to WAP enabled mobile devices. The underlying protocols in WAP technology are WCMP, WDP, WTLS and WML. Users using WAP services were charged by the time duration of data transfer. WAP requires a WSP (Wireless Service Provider) who converts http into WAP requests and transforms HTML content of the web into WML content which can be viewed on mobile phone screens. WSPs are connected to WAP Content Providers (also known as Origin Servers) who provide WAP content to WAP users. Ethernet Protocol Ethernet refers to the family of Local Area Network products covered by the IEEE 802.3 standards that defines the protocol CSMA/CD (Carrier Sense Multiple Access / Collision Detection). The three data transmission rates associated with Ethernet are: 10 Mbps (10 Base-T Ethernet) 100 Mbps (Fast Ethernet) 1000 Mbps (Gigabit Ethernet)




Q19

Explain Office Automation? HOMEWORK

(Ans 19) The use of computer systems to execute a variety of office operations, such as word processing, accounting, and e-mail. Office automation almost always implies a network of computers with a variety of available programs.

The integration of office information functions, including word processing, data processing, graphics, desktop publishing and e-mail. The backbone of office automation is a LAN, which allows users to transmit data, mail and even voice across the network. All office functions, including dictation, typing, filing, copying, fax, Telex, microfilm and records management, telephone and telephone switchboard operations, fall into this category. Office automation was a popular term in the 1970s and 1980s as the desktop computer exploded onto the scene.

Automation refers to the use of computers and other automated machinery for the execution of business-related tasks. Automated machinery may range from simple sensing devices to robots and other sophisticated equipment. Automation of operations may encompass the automation of a single operation or the automation of an entire factory.

There are many different reasons to automate. Increased productivity is normally the major reason for many companies desiring a competitive advantage. Automation also offers low operational variability. Variability is directly related to quality and productivity. Other reasons to automate include the presence of a hazardous working environment and the high cost of human labor. Some businesses automate processes in order to reduce production time, increase manufacturing flexibility, reduce costs, eliminate human error, or make up for a labor shortage. Decisions associated with automation are usually concerned with some or all of these economic and social considerations.

For small business owners, weighing the pros and cons of automation can be a daunting task. "Failure to take a strategic look at where the organization wants to go and then capitalizing on the new technologies available will hand death-dealing advantages to competitorstraditional and unexpected ones."

Types of Automation

Although automation can play a major role in increasing productivity and reducing costs in service industriesas in the example of a retail store that installs bar code scanners in its checkout lanesautomation is most prevalent in manufacturing industries. In recent years, the manufacturing field has witnessed the development of major automation alternatives. Some of these types of automation include:

Information technology (IT) Computer-aided manufacturing (CAM) Numerically controlled (NC) equipment Robots Flexible manufacturing systems (FMS) Computer integrated manufacturing (CIM)




Information technology (IT) encompasses a broad spectrum of computer technologies used to create, store, retrieve, and disseminate information.

Computer-aided manufacturing (CAM) refers to the use of computers in the different functions of production planning and control. CAM includes the use of numerically controlled machines, robots, and other automated systems for the manufacture of products. Computer-aided manufacturing also includes computer-aided process planning (CAPP), group technology (GT), production scheduling, and manufacturing flow analysis. Computer-aided process planning (CAPP) means the use of computers to generate process plans for the manufacture of different products. Group technology (GT) is a manufacturing philosophy that aims at grouping different products and creating different manufacturing cells for the manufacture of each group.

Numerically controlled (NC) machines are programmed versions of machine tools that execute operations in sequence on parts or products. Individual machines may have their own computers for that purpose; such tools are commonly referred to as computerized numerical controlled (CNC) machines. In other cases, many machines may share the same computer; these are called direct numerical controlled machines.

Robots are a type of automated equipment that may execute different tasks that are normally handled by a human operator. In manufacturing, robots are used to handle a wide range of tasks, including assembly, welding, painting, loading and unloading of heavy or hazardous materials, inspection and testing, and finishing operations.

Flexible manufacturing systems (FMS) are comprehensive systems that may include numerically controlled machine tools, robots, and automated material handling systems in the manufacture of similar products or components using different routings among the machines.

A computer-integrated manufacturing (CIM) system is one in which many manufacturing functions are linked through an integrated computer network. These manufacturing or manufacturing-related functions include production planning and control, shop floor control, quality control, computer-aided manufacturing, computer-aided design, purchasing, marketing, and other functions. The objective of a computer-integrated manufacturing system is to allow changes in product design, to reduce costs, and to optimize production requirements.

Automation and the Small Business Owner

Understanding and making use of automation-oriented strategic alternatives is essential for manufacturing firms of all shapes and sizes. It is particularly important for smaller companies, which often enjoy inherent advantages in terms of operational nimbleness. But experts note that whatever your company's size, automation of production processes is no longer sufficient in many industries.

"The computer has made it possible to control manufacturing more precisely and to assemble more quickly, factors which have increased competition and forced companies to move faster in today's market, Now, with the aid of the computer, companies will have to move to the next logical step in automationthe automatic analysis of data into information which empowers employees to immediately use that information to control and run the factory as if they were running their own business. Small business owners face challenges in several distinct areas as they prepare their enterprises for the technology-oriented environment in which the vast majority of them will operate. Three primary issues are employee training, management philosophy, and financial issues.




Challenges that come with automation

1. Employee training 2. Management Philosophy 3. Financial Issues

Employee Training: Many business owners and managers operate under the assumption that acquisition of fancy automated production equipment or data processing systems will instantaneously bring about measurable improvements in company performance. But as countless consultants and industry experts have noted, even if these systems eliminate work previously done by employees, they ultimately function in accordance with the instructions and guidance of other employees. Therefore, if those latter workers receive inadequate training in system operation, the business will not be successful. All too often, wrote Lura K. Romei in Modern Office Technology, "the information specialists who designed the software and installed the systems say that the employees are either unfamiliar with technology or unwilling to learn. The employees' side is that they were not instructed in how to use the system, or that the system is so sophisticated that it is unsuited to the tasks at hand. All the managers see are systems that are not doing the job, and senior management wonders why all that money was spent for systems that are not being used."

An essential key to automation success for small business owners, then, is to establish a quality education program for employees, and to set up a framework in which workers can provide input on the positive and negative aspects of new automation technology. As John Hawley commented in Quality Progress, the applications of automation technology may be growing, but the human factor still remains paramount in determining organizational effectiveness.

Management Philosophy: Many productive business automation systems, whether in the realm of manufacturing or data processing, call for a high degree of decision-making responsibility on the part of those who operate the systems. As both processes and equipment become more automatically controlled, Employees will be watching them to make sure they stay in control, and fine tune the process as need. These enabler tools are changing the employee's job from one of adding touch labor to products to one of monitoring and supervising an entire process."

But many organizations are reluctant to empower employees to this degree, either because of legitimate concerns about worker capabilities or a simple inability to relinquish power. In the former instance, training and/or workforce additions may be necessary; in the latter, management needs to recognize that such practices ultimately hinder the effectiveness of the company. "The people aspect, the education, the training, the empowerment is now the management issue," Flaig told Jasany. "Management is confronted today with the decision as to whether or not they will give up perceived power, whether they will make knowledge workers of these employees."

Financial Issues: It is essential for small businesses to anticipate and plan for the various ways in which new automation systems can impact on bottom-line financial figures. Factors that need to be weighed include tax laws, long-term budgeting, and current financial health. Depreciation tax laws for software and hardware are complex, which leads many consultants to recommend that business owners use appropriate accounting assistance in investigating their impact. Budgeting for automation costs can be complex as well, but as with tax matters, business owners are




encouraged to educate themselves. With the shortened life of most new technology, especially at the desktop, it is critical that you plan on annually reinvesting in your technology. You'll also need to decide what is an appropriate level of spending for your company, or for yourself if it's a personal decision. Arriving at that affordable spending level requires a strategic look at your company to assess how vital a contributor technology is to the success of your business."

Once new automation systems are in operation, business owners and managers should closely monitor financial performance for clues about their impact on operations. "Unused technology or underused technology is a big tipoff that something is wrong. Watch for cost overruns on new systems, and look out when new systems are brought in predictably late."

The accelerating pace of automation in various areas of business can be dizzying. It will be a challenge for small businesses to keep paceor stay aheadof such changes. But the forward-thinking business owner will plan ahead, both strategically and financially, to ensure that the evermore automated world of business does not leave him or her behind.




Q20 Q21 Q22 Q23 Q24 Q60 Q92 (e)

Explain Operational Feasibility & Economic Feasibility? Describe the steps in the System Development Life Cycle (SDLC) clearly specifying the activities in each stage? What are the stages in the System Development Life Cycle (SDLC)? Describe the activities in each stage? Enumerate the stages in a SDLC. Clearly mention the inputs, outputs and activities with respect to each stage? Enumerate the inputs, activity and output of each stage in a systems development life cycle? Define Feasibility Studies? Explain the following terms: Feasibility Study

(Ans 20 24, 60, 92 e) System Development Life Cycle (a.k.a. Software Development Life Cycle)

The Software Development Life Cycle (SDLC) method is an approach to developing an

Information system / software product that is characterized by a linear sequence of steps that

progress from Start to Finish without revisiting any previous step.

This methodology ensures that systems are designed and implemented in a methodical, logical

and step-by-step approach. It is the oldest and most widely used systems development models.

It consists of the following activities, namely:

1) Preliminary Investigation

2) Determination of System Requirements (a.k.a. Requirements Analysis Phase)

3) Design of the System

4) Development of the Software

5) System Testing

6) Implementation and Evaluation

7) Review

A) Preliminary Investigation Phase:

This phase begins with a phone call from the customer by way of either a memorandum from the top management to the Director of Systems Development, or by way of a letter

or an initiative from a customer to discuss a perceived problem or deficiency or by way of

a request for something new in an existing system.




Here the purpose of this step is not to develop a system but to verify that a problem or deficiency really exists or to pass a judgment on the new requirement.

Here the investigator considers the financial costs of completing the project versus the benefits of completing it.

There are three factors in this process which is also typically called Feasibility Study Process in

which the investigator tries to evaluate the Technical, Economic and Operational feasibility of the

project.

a) Technical Feasibility - This feasibility study assesses whether the current technical resources and skills

are sufficient for the new system or not.

- If they are not available, then how easy it is to obtain them, or if they exist, how

can they be upgraded to help create the new system.

- It considers the existing system and to what extent it can support the proposed

addition or enhancements.

b) Economic Feasibility - This feasibility study examines the benefits of the new system to make costs

acceptable.

- It determines whether time and money are available to develop it.

- It includes purchase of new equipment, hardware, software etc.

c) Operational Feasibility - This feasibility study determines the human resources available to operate it

once it is installed.

- Whether the system will be used if it is developed and implemented or will there

be resistance from users?

- It should be noted that users that do not want a new system may prevent it from

being operationally feasible.

Deliverables for this phase: Feasibility Reports Document




B) Requirements Analysis Phase (a.k.a. Requirements Gathering Phase)

It is a study of current business system and the users requirements and priorities for a new or improved application.

Analysts study the domain and the problem / requirements in detail. The key to make this phase a success is by gaining a rigorous understanding of

the problem or opportunity driving the need for the new system.

Close interaction with the employees (end users), managers to get details of the business process and their opinions / issues.

System Analysts should not only focus on the current problems but should closely inspect various documents related to operations and processes which are

closely related.

The System Analyst needs to have a futuristic perspective and apply it to the problem at hand.

System Analyst needs to help the user visualize the system In this phase the System Analyst usually recommends more than one alternative

for the problem resolution.

The System Analyst works closely with the Information Architect to create the prototypes and walk users through them.

The System Analyst must have strong People as well as Technical skills, as he would be required to work with clients which would put his communication and

interpersonal skills to the test and that he could better understand and identify

problems, and on the other hand his technical skill sets would help him resolve

conflicting objectives and document the requirements with process, data and

network models.

Deliverables for this phase: System Requirements Specification Document (SRS) containing Business Use Cases, Project Charter / Goals / Statement of Work (SoW), Document containing Inputs and Outputs to the system & Process Methodology. This phase covers all major details of the system or program to be built.




C) Design of the System

This phase produces details stating how the system will meet requirements identified during system analysis. This stage is known as a logical design.

This logical design involves components like Input, Output, Processing, Files etc. At the end of this phase the logical design is validated with the client and a

Functional Requirements Specification (FRS) is prepared along with the rough

sketch of what the User Interface (UI) will look like.

In this phase most programs are designed by first determining the desired output of the program. If you know the desired output, you can determine the necessary

input needed to generate such a kind of output.

In this phase the User Interface (UI) Prototype usually goes through a number of iterations.

The focus here is still on NOT discussing How or What the problem will do, but just to capture every requirement on paper.

Here the User Interface designers aid the developers with html, style guides etc.

Deliverables for this phase: Formal Requirements Specification, Rough Sketch of the UI Prototype.

D) Development of the Software

This phase is the most exciting time of the SDLC. During this phase the computer hardware is purchased, licensed software is

purchased and the coding for the development of the software actually begins.

There is adherence to the SRS (System Requirements Specification) Any deviations should be approved by either the Project Manager or the Client This phase is usually split into Prototyping & Production Quality Application

Creation.

Developers use this stage to demo the application to the customer as another check that the final software solution answers the problem posed.

Deliverables for this phase: Revised UI Prototype, Production Quality Code.




E) System Testing

The system is used experimentally to ensure whether the software runs as per the specs and in the way the Customer / End User really wanted.

Special Test Data is prepared and used and the results are examined. Bugs or deviations are identified and corrected before the system is given to the

user for the UAT (User Acceptance Testing)

User Testing helps uncover many bugs / irregularities. System is tested for its performance, reliability, functionality, scalability etc.

Deliverables for this phase: Test Plan and Test Cases.

F) Implementation and Evaluation

After the development phase of the SDLC is complete, the system is implemented.

Any hardware that has been purchased will be delivered and installed. The software which has been designed and developed in the earlier phases will

now be installed on the computers that require it.

Users required to use the program will also be trained on how to use it in this phase.

During the implementation phase, both the hardware and software are tested. Although the programmer will find and fix problems

The old system can be gradually or instantly replaced. Evaluation

Evaluation of the system is performed to identify the strengths and weaknesses of the new system. The actual evaluation can be any of the following:

1. Operational Evaluation

Assessment of the manner in which the system functions,

including the ease of use, response time, suitability of

information formats, overall reliability and level of utilization.

2. Organizational Impact Identification and measurement of benefits of the organization in

such areas as financial concerns (cost, revenue and profits),




operational efficiency and competitive impact.

3. User Manager Assessment Evaluation of the attitudes of Senior and User Managers within

the organization as well as end users.

4. Development Performance Evaluation of the development process in accordance with such

yardsticks as overall development time and effort, conformance

to budgets and standards, other project management criteria.

Includes assessment of development methods and tools.

Deliverables for this phase: All of the above + User Guides + Training Manuals.

G) Review

Review is important to gather information for maintenance of the system. No system is ever complete. It has to be maintained as changes are required

because of internal developments such as new users of business activities, and

external developments such as Industry standards or competition.

The implementation review provides the first source of Information for maintenance requirement. The most fundamental concern during post

implementation review is in determining whether the system has met its

objectives.

The Analysts assess the users performance levels and optimum quality of the system.




Q25 Q26 Q27 Q28 Q35 Q36 Q37

Computers & communications seem to merge together seamlessly. Discuss? Why are the computer and computer related devices networked in an organization? What are the benefits of networking? An integrated companywide computerization is the only way of deriving full benefits of Information technology today. Discuss? What is networking? Describe the benefits of networking with examples? Why are computers and computer related devices networked in an organization?

(Ans 25, 26, 27, 28, 35, 36, 37) Definition of Networking Networking can be explained as the linking of a number of devices, such as computers, workstations, printers, and Audio Video gear into a network (system) for the purpose of sharing resources and exchange of information between them. A network is not just a bunch of computers with wires running between them. When properly implemented, a network is a system that provides its users with unique capabilities, above and beyond what the individual machines and their software applications can provide. Most of the benefits of networking can be divided into two generic categories: connectivity and sharing. Networks allow computers, and hence their users, to be connected together. They also allow for the easy sharing of information and resources, and cooperation between the devices in other ways. Since modern business depends so much on the intelligent flow and management of information, this tells you a lot about why networking is so valuable. Here are some of the specific advantages generally associated with networking: a) Connectivity and Communication: Networks connect computers ad the users of those computers. Individuals within a building or work group can be connected into local area networks (LANs); LANs in distant locations can be interconnected into larger wide area network (WANs). Once connected, it is possible for network users to communicate with each other using technologies such as electronic mail. This makes the transmission of business (or non-business) information easier, more efficient and less expensive than it would be without the network. Today people and processes have come together via the emergence of networks. The advent of 3G and 4G technologies have enabled audio, video, text, rich media to converge and allow for seamless communication and interaction. b) Data Sharing: One of the most important uses of networking is to allow the sharing of data. Before networking was common, an accounting employee who wanted to prepare a report for her manager would have to produce it on his PC, put it on a floppy disk and then walk it over to the manager, who would transfer the data to his or her PCs hard disk. Today true networking allows thousands of employees to share data much more easily and quickly than this. More so, it makes possible applications that rely on the ability of many people to access and share the same data, such as




databases, group software development, and much more. Intranets and extranets can be used to distribute corporate information between sites and to business partners. c) Hardware Sharing: Networks facilitate the sharing of hardware devices. For example, instead of giving each of 10 employees in a department an expensive color printer, one printer can be placed on the network for everyone to share. d) Internet Access: The internet is itself an enormous network, so whenever you access the Internet, you are using a network. The significance of the Internet on modern society is hard to exaggerate, especially for those of us in technical fields. e) Internet Access Sharing: Small computer networks allow multiple users to share a single Internet connection. Special hardware devices allow the bandwidth of the connection to be easily allocated to various individuals as they need it, and permit an organization to purchase one high-speed connection instead of many slower ones. f) Data Security, Data Backup and Management: In a business environment, a network allows the administrators to much better manage the companys critical data. Instead of having this data spread over dozens or even hundreds of small computers in a haphazard fashion as their users create it. Data can be centralized on shared servers. They can also be easily backed up. This makes it easy for everyone to find the data, makes it possible for the administrators to ensure that the data is regularly backed up, and also allows for the implementation of security measures to control who can read or change various pieces of critical information. g) Performance Enhancement and Balancing: Under some circumstances, a network can be used to enhance the overall performance of some applications by distributing the computation tasks to various computers on the network. h) Entertainment: Networks facilitate many types of games and entertainment. The Internet itself offers many sources of entertainment. Today many multi-player games exist that operate over a local area network. Many home networks are set up for this reason, and gaming across wide area networks (including the internet) has also become quite popular.




The ISO OSI Model for Networking

(Ans) The Open Systems Interface means a system that can communicate with any other system that follows the specified standards, formats and semantics. The Open system Interface works well because of protocols that specify how the communicating parties may communicate. The OSI Model supports two types of Protocols namely:

a) Connection Oriented: - Sender and receiver first establish a connection, possibly negotiate on a protocol - Transmit the stream of data - Release the connection when done - E.g. Telephone connection

b) Connectionless:

- No advance setup is needed - You can transmit the messages to the receiver irrespective of whether the receiver is online or offline.




Features of the OSI Model are listed below:

Consists of 7 layers. Each layer deals with a specific aspect of communication Each layer provides an interface to the layer above it. In other words each layer above

provides some support to the layer before it. Messages are sent from the top layer (i.e. Application Layer) and are passed on the next

lower layer until the message reaches the bottom layer (i.e. Physical Layer). At each level / layer, a header may be added to the message. Some layers add both a

header and a trailer. The lowest layer transmits the message over the network to the receiving machine. The

physical layer of the sender communicates with the physical layer of the receivers machine

Each layer then strips the header or trailer, handles the message using the protocol provided by the layer and passes it on the next layer above it, until it moves right up to the application layer of the receivers machine.

a) The Physical Layer: Following are the characteristics of the Physical Layer:

The physical layer is concerned with the transmission of bits It follows a two way or one way transmission It follows standard protocols which deal with electrical, mechanical and signaling

interfaces b) The Data Link Layer: Following are the characteristics of the Data Link Layer:

Handles errors in the physical layer Groups bits into frames and ensures their correct delivery Adds some bits at the beginning and end of each frame plus the checksum The Data Link Layer on the receivers machine verifies the checksum and if the checksum

is not correct, it asks for retransmission Consists of two layers (Logical Link Control) which defines how data is transferred over

the cable and provides data link service to the higher layers. The second layer is (Medium Access Control or MAC layer) which defines who can use the network when multiple computers are trying to access the network simultaneously.

c) The Network Layer: Following are the characteristics of the Network Layer:

Concerned with the transmission of packets Chooses the best path to send a packet (routing) to ensure speedy delivery of data It may be complex in a large network (e.g. Internet) It uses a connection oriented protocol called X.25 for telephone connections and also

used Internet Protocol for establishing connectionless networks. d) The Transport Layer: Following are the characteristics of the Transport Layer:




Since the network layer does not deal with lost messages, the transport layer above it ensures reliable service

This layer breaks the message from the sessions layer above it into small packets, assigns sequence number and sends them to the network layer below it for transmission over the network

This layer is also supported in the Internet Protocol suite. e) The Sessions Layer: Following are the characteristics of the Sessions Layer:

Very few applications use this. Its an enhanced version of the transport layer and helps in dialog control,

synchronization facilities. Not supported by the Internet Protocol suite

f) The Presentation Layer: Following are the characteristics of the Presentation Layer:

Very few applications use it Concerned with the semantics of the bits sent Sender can tell the receiver the format of the data that is being sent

g) The Application Layer: Following are the characteristics of the Application Layer:

This is the layer where users actual work on This layer consists of applications which communicate using protocols Email, file transfer, remote login applications use protocols like SMTP, FTP, Telnet etc.




Understanding the Network Tree

Q38 Describe similarity between bus and ring topology? Q39 Define Topology? Q40 Networks can be classified based on various criteria such as:

Geographical Spread / Distance Type of Switching Topologies Medium of Data Communications etc. Give two examples of types of networks for each classification mentioned above.

Q57 Explain Fiber Optics? Q69 What are the various options available for a company to establish network /

connectivity across its offices and branches? Q75 Explain the different transmission mediums used for networking. Q76 (a) Distinguish between Optical Fiber and Conventional Copper Cable Q86 A company has its head office in Mumbai. It has 4 regional offices that is Mumbai,

Delhi, Calcutta and Chennai with 4 branches in each region. Some of the branches do not have even basic telephone connectivity. Prepare a network plan incorporating the different technical options for connectivity.

Q93 What is networking? State any three topologies of networking. Distinguish between LAN and WAN.

(Ans 38, 39, 40, 57, 69, 75, 76a, 93) The following illustration outlines the concepts that belong to the world of networking and explains their hierarchy.

Network Tree

Medium Geographical Distance / Location

Topology Switching

Wired Wireles LAN MAN WAN SAN

Bus Ring Star Mesh

Circuit Packet

Co-Axial Cable Twisted Pair Cable Fiber Optic Cable

Infrared Blue Tooth Wi-Fi Wi-Max




Networks > Medium: Wired > Coaxial Cable A type of wire that consists of a center wire surrounded by insulation and then a grounded shield of braided wire. The shield minimizes electrical and radio frequency interference.

Coaxial cabling is the primary type of cabling used by the cable television industry and is also widely used for computer networks, such as Ethernet. Although more expensive than standard telephone wire, it is much less susceptible to interference and can carry much more data.

Features:

Used extensively in LANs. Has a single central conductor surrounded by a circular insulation layer and a conductive

shield. Offers a high bandwidth of up to 400 Mhz. Offers a high quality of data transmission Offers maximum data transfer rates of 100 Mbps

Problems:

It can have signal loss when data is sent at high frequencies




Networks > Medium: Wired > Twisted Pair Cable

Features:

Extensively used in telephone circuits where several wires are insulated and put together Offers bandwidth of around 250 KHz It has a low signal to noise ratio (crosstalk) It offers a low data transfer rate Its preferred for short distance communications Its generally used in LAN

Networks > Medium: Wired > Fiber Optic Cable

Features:

Used for applications requiring a high quality and high bandwidth of data transfer Uses light instead of electric pulses for data transmission It offers very high frequency ranges of around 20,000 MHz and higher A single fiber can support over 30,000 telephone lines




It offers data transmission rates of 400 Mbps and higher It has become very popular for LAN and MAN as well as for Intercontinental links It has a high signal to noise ratio and is very difficult to tap into the data transmission

happening inside an optic fiber Earlier its cost was a big drawback but today the use of pure plastic has made optic fiber

very economical and commercially feasible to use.

Networks > Medium: Wireless > Infrared

Infrared technology has been around for ages, and is something that weve all come to take for granted in television, VCR, DVD remote control devices.

What Infrared does?

Infrared allows transmission of data over very short distances. One cannot transmit huge amounts of data via Infrared. For example, the remote control unit and the equipment share a special radio frequency or code, which allows the remote unit to transmit a one-way signal. Just point the remote device at whatever you want to control, and press the button.

How it works?

IR technology only works over short distances of less than 25 feet, and there cant be anything solid, like walls, standing in the way as an obstacle. Infrared is a one-way communication. It requires a clear line of sight between the devices.

How it is used?

Most of todays computers and printers have built-in infrared technology that allows you to print without bulky cables. All mobile phones have infrared built in as well for allowing their users to do a data transfer with other devices like beaming addresses, notes and other data. Networks > Medium: Wireless > Bluetooth

Bluetooth wireless technology is a short-range radio technology. Bluetooth wireless technology makes it possible to transmit signals over short distances between telephones, computers and other devices and thereby simplify communication and synchronization between devices. Bluetooth is the name of a protocol for a short range (10 meter) frequency-hopping 2.4 GHz radio link between wireless devices such as a mobile phone and a PC. The idea is to make connections between different electronic items much easier and simpler, and without a lot of operator intervention. Bluetooth was launched in 1998 as a joint effort between Ericsson, IBM, Intel, Nokia and Toshiba. Over 1000 companies are now involved in the effort -- so you can see that it has stirred a lot of interest in the wireless community.

Bluetooth is similar to infrared, but taken a step further. Instead of one-way transmissions, Bluetooth allows multiple devices from multiple manufacturers to speak the same wireless language without the conflicts that are found in standard infrared. The Bluetooth standard was jointly developed by a group of key players in the technology industry to ensure compatibility between various wireless devices. It was named after the Dutch king Harald Bltand who was famous for bringing together the warring tribes of the Scandinavian region and built a strong network of allies.




What Bluetooth does?

Bluetooth operates over short distances of around 30 feet or less, and it requires a clear line of sight between the devices. Bluetooth allows you to create your own PWAN (private wireless area network) where you can hook up up to eight devices without the hassle of cables and cords. Popular day to day use of Bluetooth can be found in many of todays wireless keyboards, wireless mouse, cell phone handsets etc. How Bluetooth works? Bluetooth operates over the unlicensed 2.5 GHz radio spectrum which allows Bluetooth-enabled equipment to operate anywhere in the world. Bluetooth uses more than 71 different frequencies, which allows a signal to hop around from one frequency to another to avoid conflicts with other devices. How is Bluetooth used? Bluetooth enabled PDAs such as Pocket PC, can synchronize email, documents and contact information with a Bluetooth enabled PC without the need of cradles, cables or plugs. Bluetooth enabled mobile phones can communicate with other Bluetooth enabled devices thereby allowing data transfer. Bluetooth enabled wireless headsets can be used with a mobile phone to provide hands free usage without the hassle of cords and plugs. Like Infrared, its limitation is that it is a short range mode of communication. Networks > Medium: Wireless > Wi-Fi Wireless Ethernet or Wi-Fi is the latest standard for long-range wireless networking. It goes further and faster than Infrared or Bluetooth and does not require a clear line of sight. Wireless local area networks (WLANs) are a lot less expensive and much easier to set up than traditional wired networks. Because they are easy and inexpensive, wireless networks have become very popular for home and small business networks and have found a niche in hospitals and clinics where its important to securely connect people to shared file servers, printers, Internet connections and other resources. What does Wi-Fi do? Wi-Fi is based on the IEEE (Institute of Electronic and Electrical Engineers) 802.11 specifications. There are currently four deployed 802.11 variations, namely: 802.11(a), 802.11(b), 802.11(g) and 802.11(n). The (b) standard allows up to 11Mbps while both (a) and (g) allows up to 54 Mbps. The new (n) specification will allow even higher speeds of up to 100 Mbps and beyond. The 802.11(a) standard works in the 5GHz frequency band, and the others work in the 2.4GHz band. How does Wi-Fi work? Wi-Fi technology operates using the unlicensed radio frequencies in the 2.4GHz to 5GHz range. 2.4GHz for both the 802.11(b) and 802.11(g) and the 5GHz range for 802.11(a). The primary difference between the Wi-Fi signals and Infrared or Bluetooth is that Wi-Fi does not require the devices to have a direct line of sight. Wi-Fi transmits data over radio signals that are sent / received via little antennas that are connected to the devices.




How is Wi-Fi used? Wi-Fi technology is used to create a fast, wireless, low cost network. Notebook PCs, Laptops, Tablet PCs, desktops, handheld devices etc can now talk to each other as well as the internet using Wi-Fi. Wi-Fi networks are springing up in airports, hotels, convention centers, hospitals and health care centers. Even airplanes like Ethihad Airways have Wi-Fi access inside their airplanes. Networks > Medium: Wireless > Wi-Max

The two driving forces of modern Internet are broadband and wireless. The WiMax standard combines the two, delivering high-speed broadband Internet access over a wireless connection. WiMax is the next generation of Wi-Fi, or wireless networking technology that will connect you to the Internet at faster speeds and from much longer ranges than current wireless technology allows. WiMAX (Worldwide Interoperability for Microwave Access) is the IEEE 802.16 standards-based wireless technology that provides MAN (Metropolitan Area Network) broadband connectivity. WiMax is based on the IEEE 802.16 Air Interface Standard (AIS). WiMax delivers a point-to-multipoint architecture, making it an ideal method for carriers to deliver broadband to locations where wired connections would be difficult or too costly. It may also provide a useful solution for delivering broadband to rural areas where high-speed lines have not yet become available. A WiMax connection can also be bridged or routed to a standard wired or wireless Local Area Network (LAN).




The so-called last mile of broadband is the most expensive and most difficult for broadband providers, and WiMax provides an easy solution. Although it is a wireless technology, unlike some other wireless technologies, it doesnt require a direct line of sight between the source and endpoint, and it has a service range of 30 miles. It provides a shared data rate of up to 70 Mbps, which is enough to service up to a thousand homes with high-speed access. WiMax offers some advantages over WiFi, a similar wireless technology; in that it offers a greater range is more bandwidth efficient. Ultimately, WiMax may be used to provide connectivity to entire cities, and may be incorporated into laptops to give users an added measure of mobility. WiMax requires a tower, similar to a cell phone tower, which is connected to the Internet using a standard wired high-speed connection, such as a T3 line. But as opposed to a traditional Internet Service Provider (ISP), which divides that bandwidth among customers via wire, it uses a microwave link to establish a connection. Because WiMax does not depend on cables to connect each endpoint, deploying WiMax to an entire high rise, community or campus can be done in a matter of a couple of days, saving significant amounts of manpower. Networks > Geographical Spread / Distance: Local Area Network (LAN) Networks can be divided into three types based on geographical areas covered, namely: LANs, MANs and WANs LAN: Local Area Network

Features:

1) LAN typically connects computers within a single building or campus. 2) LAN was developed in 1970s 3) Its restricted in size and hence the worst case transmission time is known in

advance 4) It uses a single cable transmission technology to which all computers are

attached 5) The medium used here is optical fibers, coaxial cables, twisted pair, wireless 6) It offers low latency (delay) except during peak traffic periods 7) LANs are high speed networks with data transmission speeds ranging from 0.2 to

100Mbps 8) The LAN speeds are adequate for most of the distributed systems 9) LANs use Ethernet as their protocol




Networks > Geographical Spread / Distance: Metropolitan Area Network (MAN) Features:

1) MAN generally covers towns and cities (50 kms) 2) Developed in 1980s 3) The Medium used in MAN are optic fibers and cables 4) MAN offers data transmission rates that are adequate for distributed computing 5) Supports Data and Voice (e.g. Local Cable TV) 6) MAN has one or two cables and no switching elements 7) MAN has a broadcast medium to which all computers are attached 8) IT is a simple network design 9) MAN offers typical latencies of less than 1 msec (millisecond) 10) Message routing in a MAN is fast

Networks > Geog