COMPUTER PROGRAMME

What is a Programming Language?
• Programming language is a set of words, symbols, and codes that enables a programmer to communicate a solution algorithm to a computer.
• It is needed to allow human begins and computers to talk to each other.
• A programmer can use a variety of programming languages to code a program.
• A program development tool consists of user-friendly software products designed to assist both programmers and non-technical users with the creation of information system solutions.
Traits often considered important for constituting a programming language:
• Function: A programming language is a language used to write computer programs, which involve a computer performing some kind of computation or algorithm and possibly control external devices such as printers, robots, and so on.
• Target: Programming languages differ from natural languages in that natural languages are only used for interaction between people, while programming languages also allow humans to communicate instructions to machines. Some programming languages are used by one device to control another. For example PostScript programs are frequently created by another program to control a computer printer or display.
• Constructs: Programming languages may contain constructs for defining and manipulating data structures or controlling the flow of execution.
• Expressive power: The theory of computation classifies languages by the computations they are capable of expressing. All Turing complete languages can implement the same set of algorithms. ANSI/ISO SQL and Charity are examples of languages that are not Turing complete yet often called programming languages.
Some authors restrict the term "programming language" to those languages that can express all possible algorithms; sometimes the term "computer language" is used for more limited artificial languages.
Non-computational languages, such as markup languages like HTML or formal grammars like BNF, are usually not considered programming languages. A programming language (which may or may not be Turing complete) may be embedded in these non-computational (host) languages.

Generation of Programming Language

• The first generation of language was the machine language. The machine language instruction uses a series of binary digits or a combination of numbers and letters that represents binary digits. Instructions and addresses were numerical.
• The second generation of language was the symbolic instructions or mnemonics and addresses. To convert the assembly language source program into machine language, you use an assembler. Example, IBM, BAL and VAX macro.
• The third generation language was the programmer concentration of structured programming and database management. It is a procedural language that requires the program instruction to tell the computer what to accomplish and how to do it. Example, FORTRAN, ADA, COBOL, Pascal, C and BASIC.
• The fourth generation (4GL) was the non-procedural type language. The programmer only specifies what the program should accomplish without explaining how. Example. SQL, Postscript, and relational database orientation.
• The fifth generation (5GL) was concerned on Artificial Intelligence and Fuzzy Logic.



Advantages and disadvantages of each generation of language

• Readability of the language
 If parts of the program are going to be read or altered separately form the entire program is might be worth considering how legible they are going to be. Clumsy abbreviations should be avoided. Statements such as WHILE LOOP have increased the readability of programs and lead to neater programs.

• Ease of writing the language
 A programming language that is easy to write in can make the process easier and faster. It may help to reduce mistakes, save time and money, and make the program smaller.

• Reliability of the language
 A program that is not robust can cause errors, and code can “decay”. Any language that helps the programmer to avoid mistakes will make it easier to use.

• Cost of development
 Is the language expensive to use and to maintain? Program may need to be updated or re-developed and an expensive language may make this prohibitive.

• Syntax complexity
 Syntax is an important consideration. Clarity and ease of understanding are important, as is a syntax that seems logical and sensible. Errors are very likely to occur where one area of syntax too closely resembles another, and the program may prove difficult to debug.

• Language standards
 Languages that have standards for writing programs have greater readability.

Language Models

• Imperative Languages – are formed from collections of basic commands, most often assignments and I/O, where the execution is sequenced by control structures.

• Functional Languages – are based on lambda-calculus from the 1930’s. Programs consist of collections of function definitions and function applications.


• Logic Programming – consists of collections of statements within a particular logic. Most typically that logic is predicate logic. ProLog.

• Object-oriented languages – Programs consist of objects that interact with each other. Some also associate inheritance and polymorphism with OO language. Smalltalk, Java.

• Declarative languages – are collections of declarations. Many functional and logic languages are also declarative. Declarative languages describe relationships between variables in terms of functions or inference rules and the language executor applies some fixed algorithm to these relations to produce a result.

• Scripting language – work in conjunction with a larger application, support control of a variety of applications, are interpreted, or some combination thereof.

• Parallel language – are collections of processes that communicate with each other.

Objectives
• Getting students to understand the objectives of the subject, and also including marks distribution for the subject.
• Review historical development of computer systems
• Identify design levels for computer system development
• Discuss descriptive and design tools for each design level
• Compare and contrast various performance metrics for computer systems

Computer Architecture
• Baer: “The design of the integrated system which provides a useful tool to the programmer”
• Hayes: “The study of the structure, behaviour and design of computers”
• Abd-Alla: “The design of the system specification at a general or subsystem level”
• Foster: “The art of designing a machine that will be a pleasure to work with”
• Hennessy and Patterson: “The interface between the hardware and the lowest level software”

• Computer architecture refers to those attributes of the system that are visible to a programmer -- those attributes that have a direct impact on the execution of a program
– Instruction sets
– Data representations
– Addressing
– I/O
• Synonymous with “architecture” in many uses and textbooks
• We will use it to mean the underlying implementation of the architecture
• Transparent to the programmer
• An architecture can have a number of organisational implementations
– Control signals
– Technologies
• Device implementations

Structure and Functions
• Structure is the way in which components relate to each other
• Function is the operation of individual components as part of the structure


Computer Functions
• Historically, a computer was a job title, not a piece of equipment!
• Requirements of a computer:
– Process data
– Store data
– Move data between the computer and the outside world
• Control the operation of the above

Functional View


Evolution of Digital Computers

Operations (1) Data movement



Operations (2) Storage



Operation (3) Processing from/to storage



Operation (4) Processing from storage to I/O



Structure - Top Level



Structure - The CPU



Structure - The Control Unit

A. Learning Objectives

1. Defining Operating System.
2. Identify the various types of OS and discuss the features of the each type

B. Learning Outcomes

1. Identify the various types of OS and discuss the features of the each type
2. To identify the key features of the each types of OS

Objectives
 To provide a grand tour of the major operating systems components
 To provide coverage of basic computer system organization

What is an Operating System?
 A program that acts as an intermediary between a user of a computer and the computer hardware.
 Operating system goals:
 Execute user programs and make solving user problems easier.
 Make the computer system convenient to use.
 Use the computer hardware in an efficient manner.

Computer System Structure
 Computer system can be divided into four components
 Hardware – provides basic computing resources
 CPU, memory, I/O devices
 Operating system
 Controls and coordinates use of hardware among various applications and users
 Application programs – define the ways in which the system resources are used to solve the computing problems of the users
 Word processors, compilers, web browsers, database systems, video games
 Users
 People, machines, other computers

Four Components of a Computer System


Operating System Definition

 OS is a resource allocator
 Manages all resources
 Decides between conflicting requests for efficient and fair resource use
 OS is a control program
 Controls execution of programs to prevent errors and improper use of the computer
 No universally accepted definition
 “Everything a vendor ships when you order an operating system” is good approximation
 But varies wildly
 “The one program running at all times on the computer” is the kernel. Everything else is either a system program (ships with the operating system) or an application program

Computer Startup
 bootstrap program is loaded at power-up or reboot
 Typically stored in ROM or EPROM, generally known as firmware
 Initializates all aspects of system
 Loads operating system kernel and starts execution

Computer System Organization
 Computer-system operation
 One or more CPUs, device controllers connect through common bus providing access to shared memory
 Concurrent execution of CPUs and devices competing for memory cycles



Computer-System Operation
 I/O devices and the CPU can execute concurrently.
 Each device controller is in charge of a particular device type.
 Each device controller has a local buffer.
 CPU moves data from/to main memory to/from local buffers
 I/O is from the device to local buffer of controller.
 Device controller informs CPU that it has finished its operation by causing an interrupt.

Common Functions of Interrupts
 Interrupt transfers control to the interrupt service routine generally, through the interrupt vector, which contains the addresses of all the service routines.
 Interrupt architecture must save the address of the interrupted instruction.
 Incoming interrupts are disabled while another interrupt is being processed to prevent a lost interrupt.
 A trap is a software-generated interrupt caused either by an error or a user request.
 An operating system is interrupt driven.

Interrupt Handling
 The operating system preserves the state of the CPU by storing registers and the program counter.
 Determines which type of interrupt has occurred:
 polling
 vectored interrupt system
 Separate segments of code determine what action should be taken for each type of interrupt

Interrupt Timeline


I/O Structure
 After I/O starts, control returns to user program only upon I/O completion.
 Wait instruction idles the CPU until the next interrupt
 Wait loop (contention for memory access).
 At most one I/O request is outstanding at a time, no simultaneous I/O processing.
 After I/O starts, control returns to user program without waiting for I/O completion.
 System call – request to the operating system to allow user to wait for I/O completion.
 Device-status table contains entry for each I/O device indicating its type, address, and state.
 Operating system indexes into I/O device table to determine device status and to modify table entry to include interrupt.

Two I/O Methods (a) Synchronous (b) Asynchronous


Device-Status Table


Direct Memory Access Structure
 Used for high-speed I/O devices able to transmit information at close to memory speeds.
 Device controller transfers blocks of data from buffer storage directly to main memory without CPU intervention.
 Only one interrupt is generated per block, rather than the one interrupt per byte.

Storage Structure
 Main memory – only large storage media that the CPU can access directly.
 Secondary storage – extension of main memory that provides large nonvolatile storage capacity.
 Magnetic disks – rigid metal or glass platters covered with magnetic recording material
 Disk surface is logically divided into tracks, which are subdivided into sectors.
 The disk controller determines the logical interaction between the device and the computer.

Storage Hierarchy
 Storage systems organized in hierarchy.
 Speed
 Cost
 Volatility
 Caching – copying information into faster storage system; main memory can be viewed as a last cache for secondary storage.

Storage-Device Hierarchy


Caching
 Important principle, performed at many levels in a computer (in hardware, operating system, software)
 Information in use copied from slower to faster storage temporarily
 Faster storage (cache) checked first to determine if information is there
 If it is, information used directly from the cache (fast)
 If not, data copied to cache and used there
 Cache smaller than storage being cached
 Cache management important design problem
 Cache size and replacement policy

Performance of Various Levels of Storage
 Movement between levels of storage hierarchy can be explicit or implicit


Operating System Structure

 Multiprogramming needed for efficiency
 Single user cannot keep CPU and I/O devices busy at all times
 Multiprogramming organizes jobs (code and data) so CPU always has one to execute
 A subset of total jobs in system is kept in memory
 One job selected and run via job scheduling
 When it has to wait (for I/O for example), OS switches to another job
 Timesharing (multitasking) is logical extension in which CPU switches jobs so frequently that users can interact with each job while it is running, creating interactive computing
 Response time should be < 1 second
 Each user has at least one program executing in memory process
 If several jobs ready to run at the same time  CPU scheduling
 If processes don’t fit in memory, swapping moves them in and out to run
 Virtual memory allows execution of processes not completely in memory

Advantages and disadvantages of each generation of language

• Readability of the language
 If parts of the program are going to be read or altered separately form the entire program is might be worth considering how legible they are going to be. Clumsy abbreviations should be avoided. Statements such as WHILE LOOP have increased the readability of programs and lead to neater programs.

• Ease of writing the language
 A programming language that is easy to write in can make the process easier and faster. It may help to reduce mistakes, save time and money, and make the program smaller.

• Reliability of the language
 A program that is not robust can cause errors, and code can “decay”. Any language that helps the programmer to avoid mistakes will make it easier to use.

• Cost of development
 Is the language expensive to use and to maintain? Program may need to be updated or re-developed and an expensive language may make this prohibitive.

• Syntax complexity
 Syntax is an important consideration. Clarity and ease of understanding are important, as is a syntax that seems logical and sensible. Errors are very likely to occur where one area of syntax too closely resembles another, and the program may prove difficult to debug.

• Language standards
 Languages that have standards for writing programs have greater readability.

Language Models

• Imperative Languages – are formed from collections of basic commands, most often assignments and I/O, where the execution is sequenced by control structures.

• Functional Languages – are based on lambda-calculus from the 1930’s. Programs consist of collections of function definitions and function applications.


• Logic Programming – consists of collections of statements within a particular logic. Most typically that logic is predicate logic. ProLog.

• Object-oriented languages – Programs consist of objects that interact with each other. Some also associate inheritance and polymorphism with OO language. Smalltalk, Java.

• Declarative languages – are collections of declarations. Many functional and logic languages are also declarative. Declarative languages describe relationships between variables in terms of functions or inference rules and the language executor applies some fixed algorithm to these relations to produce a result.

• Scripting language – work in conjunction with a larger application, support control of a variety of applications, are interpreted, or some combination thereof.

• Parallel language – are collections of processes that communicate with each other.

Introduction
The Integrated System Project (ISP) undertaken by students in the final year of their Diploma in Computer Studies is the major assignment required to be submitted for the project course that is relevant to their particular program of study. These 05-credit courses extend across the two semesters in the final year of the diploma.

The ISP
An ISP is a sustained piece of work carried out by student which when completed, will reflect the student’s ability to tackle a selected problem in depth and to present their findings in a technical report.

Choose an ISP Title
In the majority of cases, students will decide upon a specific project or project area, and discuss the feasibility of a particular project idea with a member of the academic staff. Students may request to have the opportunity to work on projects related to an area pursued by a member of academic staff, in which case, students will be interviewed for their suitability.

Finding a supervisor
In the first instance you should discuss any ideas for a project with a member of the academic staff. You should do your best to secure the agreement of a member of academic staff to supervise your project. A supervisor will be allocated to you if you are not successful in finding a member of the academic staff to agree to supervise your proposed project.
Meeting supervisor
Regular meetings are essential. Short meetings held every week for the first few weeks will help you to fully establish the details of your proposed project. The frequency of meetings may then reduce to fortnightly or every few weeks depending upon circumstances. On a weekly basis, the amount of time that could be spent with each student is very limited. You should endeavour to plan your project activities to include checkpoints at which times you would have something useful prepared for a meeting with your supervisor. Nevertheless, regular contact throughout the year is essential if your supervisor is to gain a good idea of the work that you put into the development of the project - a factor which will influence the mark that you are eventually awarded for your development work! In the case of part-time students, it may be hard to arrange meetings with the supervisor; less frequent meetings in person may be adequate if frequent contact is made by other means, e.g. telephone, mail, or electronic mail. This may also apply to full-time students if the supervisor is agreeable.

Assessing ISP
Assessment is based on your development work over the period of the project and the final work. The final work may consist of a product and project report. Your supervisor is responsible for assigning a development mark that reflects the work that you have put into the project during the year, and also the way in which you have approached the topic and dealt with the concepts and any problems that may have arisen. For this reason and other reasons that should be self-evident, you should keep your supervisor informed of your progress at regular intervals.

The ISP Report
The project report is a report that you write to record and present the work that you have done and the conclusions that you have reached. It is read and assessed for its clarity and comprehension by both your supervisor and another member of the academic staff who will each award a mark for the project report. The report must be word-processed. Two copies of the report are needed. Planning the shape of the report (e.g. deciding upon chapter headings and their ordering) should commence before the end of the first semester. You will be advised in detail during the project lectures concerning appropriate logical structuring and physical layout of the report. One copy of the completed, unbound project report must be submitted on or before the deadline.

Purpose of the ISP Report
The project report provides a record of the work done in the project, which may serve as a starting point for other projects in subsequent years. The assessment of a project is based mainly on the project report. Without a report it is most unlikely that a project will achieve a pass mark (except perhaps when the absence of a report is for reasons beyond the control of the student). The project report should therefore describe the work done in the project in as favorable a way as possible, and, if the situation arises, explain why some of the intended work was not done. It is further worth bearing in mind that the project report represents probably the largest, individual piece of work carried out by a student during their diploma. Prospective employers are often keen for students recently graduated, to take their projects with them to interviews as a demonstration of ability to work independently and ability to manage their work over a period of time - qualities which are generally accepted to be very desirable in an applicant. It also provides clear evidence of their ability in written communication. Whilst good writing cannot make up for the lack of content, it is always advisable to present the contents in the best possible light by the use of good English and a correctly structured layout.

Logical Structure of the Report
The structuring and content of project reports is covered in full in the project lectures. For information only, the following may serve as a guide:
The following is the standard structure for the project report:
Title Page
Abstract
Preface … … … … … … … … .optional
Acknowledgements
Table of Contents
List of Tables… … … … … … optional
List of Figures… … … … … ...optional
Body of Report
List of References
Appendices
Glossary… … … … … … … … optional

Title Pages
The Title Page contains the project title, your name, the date (month and year) of submission (i.e. May 2008), and the title of the diploma program. There is a required ‘house style’ format for the Title Page. This is given out during the project lectures.

Abstract
The abstract, occupying less than half a page, is a short description of the intention of the project.

Preface
The Preface includes any relevant observations that do not belong in the project itself.

Acknowledgements
It is customary to acknowledge any substantial help, with either the project work or the report, from people and other informal sources.

Table of Contents
The report should be divided into chapters each of which may be divided into sections which may again be divided into subsections and so on. Each chapter and numbered section or subsection should have a title, and the contents page should list the most significant of these.

Body of report
In the body of the report, each chapter should start on a new page. Chapter headings should appear more important than section headings. This can be achieved for example by the use of different font sizes and attributes. Full direction is given in the project lectures. The following usually have one or more chapters devoted to them.

E-commerce covers any form of business transaction or information exchange that is executed using any form of information and communications technology. This embraces business-to-business; business-to-consumer; and government-to-nation; as well as exchange of tools like the Internet and the World Wide Web, intranets, extranets, electronic mail and Electronic Data Interchange. (UK’s e-centre)

· Brief history of E-Commerce;
§ look at what drives E-Commerce;
§ look at the components of an E-Commerce system;
§ list the range of E-Commerce techniques; identifying them within different business contexts;
§ start to look at the impact of E-Commerce on the organisation.

· The application of advanced information technology to increase the effectiveness of the business relationships between trading partners. (Automotive Industry Action Group in North America)

The enablement of a business vision supported by advanced information technology improves efficiency and effectiveness within the trading process. (E-Commerce Innovation Centre at Cardiff University)

The development of E-Commerce in the context of technological developments of the IT world today;

As the current environment provides affordable, more powerful and user-friendly systems, this has promoted the need of a system as a tool provider for business.

The development of EDI (Electronic Data Interchange) brought about data to transfer from one system to another. EDI was widely used in the 1980s and early 1990s. The latter developments were of the X.400 and the Internet.

2.0 Electronic commerce (E-commerce)

· The process of buying, selling, transferring, or exchanging products, services and/or information via computer networks, including the Internet

· The origins of e-commerce first started with innovations such as electronic fund transfer (EFT) in which funds could be routed electronically form one organisation to another

· Then came Electronic Data Interchange (EDI), a technology used to electronically transfer routine documents, which expanded electronic transfers from financial transactions to other types of transaction processing such as ordering

· EDI required having expensive dedicated and private lines between the trading parties

· Internet and WWW overcome the shortcomings of EDI


3.0 Electronic Business

· A broader definition of EC, includes not just the buying and selling of goods and services, but also servicing customers, collaborating with business partners, and conduction electronic transactions within an organisation.
· E-Business is the use of the Internet and other information technologies to support commerce and improve business performance.
· Some view e-business as comprising those activities that do not involve buying and selling over Internet, such as collaboration and intrabusiness activities.

4.0 Types of EC organisations

· Brick and Mortar Organization - Old-economy organizations that perform most of their business off-line, selling physical products by means of physical agents. Purely physical organization.
· Virtual (Pure-Play) Organization – Organization that conduct their business activities solely.
· Click and mortar organization – organization that conduct some e-commerce activities, but do their primary business in the physical world.

5.0 World Wide Web

· Created in the early 1990s Tim Berners-Lee
· Software that allows users to exchange information as it was designed to help scientists share online information using a single, unified interface.
· Mid-1993, Marc Andressen, an undergraduate of University of Illinois, wrote a program called Mosaic, which made using the web as easy as pointing and clicking at pictures and underlined words
· Mosaic was the first graphical browser that was launched with 150 websites holding a few thousand web-pages.
· 1995 there were about 10,000 sites, a number that had grown to 4 - 5 m by mid-1999.
· Commercial use of the Internet has skyrocketed, with companies using the Internet to communicate with each other, with their customers, with their partners and with their suppliers.
6.0 Electronic markets

Classification of EC by the nature of the transactions / interactions:
1. Business-to-business (B2B) – all of the participants are businesses or other organizations e.g suppliers

2. Business-to-Consumer (B2C) / e-tailing – includes retail transactions of products and services from businesses to individual shoppers

3. Business-to-business-to-consumer (B2B2C) – a business provides some product or service to a client business that maintain its own customers

4. Consumer-to-business (C2B) – individuals who use the Internet to sell products or services to organisations, or individuals seek sellers to bid on products or services they need

5. Consumer-to-consumer (C2B) - consumers ell directly to other consumers

6. Peer-to-peer applications – technology that enables networked peer computers to share data and processing with each other directly, can be used in C2C, B2B, and B2C ecommerce

7. Mobile-commerce (m-commerce) – e-commerce transactions and activities conducted in a wireless environment

8. Intra-business EC – includes all internal organisational activities that involve the exchange of goods, services, or information among various units and individuals in an organisation

9. Location-based commerce (l-commerce) – m-commerce transactions targeted to individuals in specific locations, at specific times

10. Business-to-employees (B2E) – organisations deliver services, information or products to its individual employees

11. Collaborative commerce (c-commerce) – individuals or groups communicate or collaborate online

12. E-learning – online delivery of information for the purposes of training or education

13. Exchange-to-exchange (E2E) – electronic exchanges formally connect to one another for the purpose of exchanging information

14. E-government – a government entity buys or provides goods services, or information to businesses (G2B)or individual citizens (G2C)


7.0 Benefits

· Global reach – expands the marketplace to national and international markets. With minimal capital outlay, a company can easily and quickly locate the best supplier, more customers, and the most suitable business partners worldwide.
· Cost reduction – decrease the cost of creating, processing, distributing, storing, and retrieving paper-based information.
· Supply chain Improvements – supply chain inefficiencies, such as excessive inventories and delivery delays can be minimized with EC.
· Extended hours – 24/7/365 the business always open on the Web, with no overtime or other extra costs.

8.0 Limitations

· costs of a technological solution
· some protocols are not standardized around the world
· reliability for certain processes
· insufficient telecommunications bandwidth
· Software tools are not fixed but constantly evolving (ie. Netscape 3,4,4.7,4.75 etc.)
· integrating digital and non-digital sales and production information
· access limitations of dial-up, cable, ISDN, wireless
· some vendors require certain software to show features on their pages, which is not common in the standard browser used by the majority
· Difficulty in integrating e-Commerce infrastructure with current organizational IT systems
9.0 E-Marketplace

An online marketplace where buyers and sellers meet to exchange goods, services, money or information.
E-markets may be supplemented by interorganizational or intraorganizational information systems.


The Internet has had such a huge impact on the world (in business, media and society) that it is easy to overlook the technology that preceded it, that enabled it and that has evolved subsequently. In eCommerce terms, though, this does not mean that this technology is any less valid. Remember, we are trying to find the right tools for the right job.

Networks
Networks are electronic/data highways which link computers together for the purpose of sharing resources. They are characterised by:

• the type of data transmission technology they use;
• whether they carry voice, data, or voice and data;
• whether they are public or private (i.e. who can use them);
• the nature of connection - dial-up, dedicated or virtual connections;
• the types of physical links (such as optical fiber, coaxial cable, and copper wire).

The type of data transmission refers to the protocol they use, i.e. the set of rules for communicating that the end points in a connection use when they exchange signals. Both endpoints must understand and observe the protocol. The Internet uses TCP/IP protocols, which includes TCP (Transmission Control Protocol) and IP (Internet Protocol), HTTP, FTP and other protocols, each with a defined set of capabilities.


Local Area Networks (LANS)
LANs link a number of computers by relatively short lengths of cable, usually within the same room or building . Typically, a more powerful computer, called a server, will serve data and applications to a number of desktop PCs. Due to the short length of the cables, data transmission is very fast (MegaBits or even GigaBits per second). Company LANs are usually controlled by a member of the IT department called the network administrator.
It is important to recognise LANs as part of the communications infrastructure because they are often the basis of a company's IT systems. As such, any implementation of eCommerce will require integration of the LAN with external communications media. A LAN that uses Internet.Protocols is, essentially, an intranet, and can support applications run on the Internet if appropriate server software is installed.
The purpose of an intranet is to allow everyone to share information and facilitate group work processes. Like any other network, it holds file directories and allows resource sharing. Intranets are still very much in their infancy as regards the level of sophistication around the types of applications and information held on them. According to recent research completed by InformationWeek the most common applications on intranets are policy and procedure manuals, document sharing and corporate phone directories.
The intranet must have a firewall to prevent unauthorised access from outside the company. Firewalls are hardware/software combinations that allow people from outside an intranet to access data on the Internet, but keep intruders from getting onto the intranet. Depending on how secure a site needs to be and how much time, money and resources can be spent on a firewall, there are many kinds that can be built. Most of them, however, incorporate the following elements:
• proxy servers;
• routers;
• bastion hosts.



Wide Area Networks (WANs)
WANs connect a number of computers, or LANs using long-distance connections. The connections may be along private cables, microwave or satellite links or may be leased from a network provider, such as an Internet Service Provider (ISP) or a telecoms operator. A WAN may contain a number of switching and relaying computers called 'nodes' or 'gateways'. A connection between two major nodes is called a 'backbone'. The Internet itself is a very large WAN. The extension of a simple LAN to the WAN is also the basis for the similar extension of the concept of the intranet to an extranet, which is a key component of business-to-business eCommerce. Essentially an extranet is a private network that uses the Internet protocols 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. Therefore, the same benefits that Internet technologies have brought to the Internet and to corporate intranets are now being made available to accelerate business between businesses.


An extranet requires security and privacy. These require firewall server management (in much the same way as intranets) and, increasingly, the use of Virtual Private Networks (VPN's - see below) that are able to tunnel securely through the public network.

The reasons why extranets are, potentially, so important to the area of business-to-business eCommerce, are that they allow organisations to:

• exchange large volumes of data using EDI;
• share product catalogues exclusively with wholesalers or distributors;
• collaborate with other companies on joint development efforts;
• jointly develop and use training programs with other companies;
• provide or access services provided by one company to a group of other companies, such as an online banking application managed by one company on behalf of affiliated banks;
• share news of common interest exclusively with trading partner companies.

Virtual Private Networks
Historically, organisations that needed to construct networks that would serve multiple sites, or maybe allow communication with their clients or suppliers, would achieve this by constructing a virtual private network,or VPN.

With the advent of the Internet, along with relatively cheap broadband access technologies, interest in constructing VPNs across the Internet has grown considerably because it has the potential to offer a VPN service at significantly lower cost than would be the case with networks constructed from dedicated leased lines. However, the very public nature of the Internet means that, although it is possible still to construct trusted VPNs in this environment, many users require a higher degree of assurance that their communications over the VPN will be secure. Hence, this has given rise to the use of technologies that allow secure VPNs to be constructed. The basic concept behind a secure VPN is that all communications taking place across the VPN are encrypted, thus preventing the data from being read in any meaningful form, even if a potential eavesdropper is able to examine the data packets being transmitted on the network. The devices communicating over the network, or the network users, or both, may well also need to be authenticated, to ensure that only trusted individuals or equipment can be attached to the network. Most current implementations of secure VPNs are based on a family of encryption technologies known as IPSec, which is used to construct a secure 'tunnel' across the Internet that can carry the client's data.

VPN technology is accessible to business users in a variety of forms. The telecommunications service providers have offered trusted VPN services for a number of years and, increasingly, are also offering secure VPN services. In both cases, the offering is a managed service, having the advantage of off-loading the maintenance and management of the network from the user. Perhaps the most interesting aspect of secure VPNs is that it is possible for these services to be provided and managed by the businesses that use them. As they rely on encryption technology that can be installed either as software in a PC or as add-ons to existing LANs, VPN services can potentially be used by all sizes of business user, from the SME up to the multi-national.
VPNs can significantly improve the security of communication within a distributed organisation. This can be important for:


• Internal communications within the organisation;
• Communications with client or trading partners, where confidentiality of commercially sensitive information may be a requirement;
• Providing secure networking for home workers.


The same secure VPN technology can also be applied as a means of overcoming the present shortcomings in wireless LAN security; if all information transmitted over the wireless LAN is properly encrypted using the IPSec mechanisms, it is no longer a concern that an eavesdropper might be able to 'see' the data packets being communicated, since it will be impossible to decrypt the data. Secure VPNs can, in many ways, be viewed as a means of making the other networking technologies safer to use in a commercial environment; hence, coupled with the other technologies mentioned in earlier sections, VPNs become an essential factor in delivering the benefits that can accrue from these technologies.
A major benefit with managed VPN services is that they significantly reduce the costs associated with constructing and managing a wide area data network. This can be significant for all sizes of business. Even the larger multinationals often cannot afford the expense of running a truly private WAN, whereas the established telecommunications suppliers can offer a managed service at a much more affordable cost.
Virtual private network technology is not only available today from companies specialising in VPNs, but also from operating system vendors (e.g. Microsoft) and traditional firewall vendors. There is limited interoperability between products from different vendors today, since standards are only now being finalised. Therefore, the user is likely to need software from the same vendor for both end points of the tunnels. The key standard that is emerging is IPsec (secure IP), whilst others include SOCKS and Layer 2 Tunneling Protocol (L2TP). The L2TP standard combines attributes of Microsoft's Point to Point Tunneling Protocol (PPTP) and Cisco's L2F (layer 2 forwarding.)
The development of E-Commerce in the context of business developments
Communication

1. Options:
• Telephone: dial-up or leased line
• ISDN: basic rate or primary rate
• Value Added Networks
• X.400: ISO standard secure messaging
• Networks: local area networks, wide area networks or intranets
• Internet: messaging, file transfer, Telnet, World Wide Web, XML

2. Standards:
• Standards are the means by which data is sent in an agreed format by eCommerce trading partners.
• In Electronic Data Interchange (EDI), standards pertain specifically to the syntax used to prepare messages for exchange. They enable, for example, one accounts system to understand an electronic version of an invoice sent out by another accounts system because the relevant pieces of data (e.g. invoice number) are always located in the same part of the message.
• In the case of EDI, these standards are generally nationally and
• The means which data is sent in an agreed format by E-commerce trading partners.
E.g.:
• EDI: syntax used to prepare message for exchange
• Gif and JPG: graphic standards
• World Wide Web:HTML, PERL, Javascript, Java, Software

3. The e-commerce software function includes:
• Data extraction from relevant application or data entry
• Data encoding to agreed standard format
• Data transmission to recipients.
• Data receipt by recipients.
• Data decoding for internal applications.
• Data insertion into relevant applications

Business-to-Business E-commerce
Key areas in B2B e-commerce:
• Electronic Data Interchange (EDI)
• Enhanced messaging: e-mail, voice-mail, fax
• Teleconferencing
• Integrated Systems: intranets/extranets, database publishing, workflow

Supply Chain E-commerce



1.0 Defining E-Commerce

• Key areas in B2B e-commerce:
1. Stock control
2. Just-in-time delivery
3. Transportation
4. Warehouse management
5. Automatic Identification: Barcodes, Transponders
Business-to-Consumer E-commerce
B2C e-commerce application includes:
1. Database application
2. Kiosks
3. Internet store fronts
4. Downloadable software and software support
5. Internet auctions
6. Advertising on the Internet
7. Interactive TV

BASIC CONCEPT OF INFORMATION TECHNOLOGY

Topic list
1 Organisational information requirements 1(a)
2 Business strategy and information systems strategy 1(a)
3 Developing a strategy for information systems and information technology 1(a)
4 Critical success factors 1(a)

Introduction
Welcome to Paper 2.1 Information Systems. This Study Text follows the structure of the officialACCA syllabus and study guide wherever possible.
The front page of each chapter provides syllabus and study guide references showing the areascovered within the chapter.
We start with a look at the concept of business strategy and strategic planning. Later in thischapter we examine the relationships between business strategy, information systems (IS) andinformation technology (IT).

Study guide
Part 1.1 - Business strategy and IS/IT alignment
• Explain an approach that an organisation may follow to formulate its strategic businessobjectives
• Discuss how information systems may be used to assist in achieving these objectives (thisissue is relevant throughout this text)
• Distinguish between a business strategy and an information systems strategy
• Identify responsibility for the ownership of the IS strategy

1 ORGANISATIONAL INFORMATION REQUIREMENTS
1.1 All organisations require information for a range of purposes. These can be categorised asfollows.
• Information for planning
• Information for controlling
• Information for recording transactions
• Information for performance measurement
• Information for decision making

Planning
1.2 Planning requires a knowledge of the available resources, possible time-scales and the likelyoutcome under alternative scenarios. Information is required that helps decision making,and how to implement decisions taken.

Controlling
1.3 Once a plan is implemented, its actual performance must be controlled. Information isrequired to assess whether it is proceeding as planned or whether there is someunexpected deviation from plan. It may consequently be necessary to take some form ofcorrective action.

Recording transactions
1.4 Information about each transaction or event is required. Reasons include:
(a) Documentation of transactions can be used as evidence in a case of dispute.
(b) There may be a legal requirement to record transactions, for example for accountingand audit purposes.
(c) Operational information can be built up, allowing control action to be taken.

Performance measurement
1.5 Just as individual operations need to be controlled, so overall performance must bemeasured. Comparisons against budget or plan are able to be made. This may involve thecollection of information on, for example, costs, revenues, volumes, time-scale andprofitability.

Decision making
1.6 Strategic planning, management control and operational control may be seen as a hierarchyof planning and control decisions. (This is sometimes called the Anthony hierarchy, afterthe writer Robert Anthony.)predicted
1.7 Strategic planning is a complex process which involves taking a view of the organisationand the future that it is likely to encounter, and then attempting to organise the structureand resources of the organisation accordingly.

Strategic information
1.8 Strategic information is used to plan the objectives of the organisation, and to assesswhether the objectives are being met in practice. Such information includes overallprofitability, the profitability of different segments of the business, future market prospects,the availability and cost of raising new funds, total cash needs, total manning levels andcapital equipment needs.

1.9 Strategic information is:
• Derived from both internal and external sources
• Summarised at a high level
• Relevant to the long term
• Concerned with the whole organisation
• Often prepared on an 'ad hoc' basis
• Both quantitative and qualitative
• Uncertain, requiring assumptions to be made regarding the future

Tactical information
1.10 Tactical information is used to decide how the resources of the business should beemployed, and to monitor how they are being and have been employed. Such informationincludes productivity measurements (output per hour) budgetary control or varianceanalysis reports, and cash flow forecasts, staffing levels and profit results within a particulardepartment of the organisation, labour turnover statistics within a department andshort-term purchasing requirements.

1.11 Tactical information is:
• Primarily generated internally (but may have a limited external component)
• Summarised at a relatively low level
• Relevant to the short- and medium-terms
• Concerned with activities or departments
• Prepared routinely and regularly
• Based on quantitative measures

Operational information
1.12 Operational information is used to ensure that specific operational tasks are planned andcarried out as intended.

1.13 In a payroll office, for example, operational information would include the hours worked byeach employee and the rate of pay per hour.

1.14 Operational information is:
• Derived from internal sources
• Detailed, being the processing of raw data
• Relevant to the immediate term
• Task-specific
• Prepared very frequently
• Largely quantitative

The qualities of good information
1.15 'Good' information is information that adds to the understanding of a situation. Thequalities of good information are outlined in the following table.


Quality Example
A ccurate
Figures should add up, the degree of rounding should beappropriate, there should be no typos, items should be allocatedto the correct category, assumptions should be stated foruncertain information.

C omplete
Information should include everything that it needs to include,for example external data if relevant, or comparative information.

C ost-beneficial
U ser-targeted
It should not cost more to obtain the information than the benefitderived from having it. Providers or information should be givenefficient means of collecting and analysing it. Presentation shouldbe such that users do not waste time working out what it means.
The needs of the user should be borne in mind, for instancesenior managers need summaries, junior ones need detail.
R elevant
Information that is not needed for a decision should be omitted,no matter how 'interesting' it may be.

A uthoritative
The source of the information should be a reliable one (not, forinstance, 'Joe Bloggs Predictions Page' on the Internet unless JoeBloggs is known to be a reliable source for that type ofinformation).
T imely
The information should be available when it is needed.
E asy to use Information should be clearly presented, not excessively long,and sent using the right medium and communication channel (e-____ ______ mail, telephone, hard-copy report etc).

Improvements to information
1.16 The table on the following page contains suggestions as to how poor information can beimproved.

Feature Example of possible improvements
Accurate Use computerised systems with automatic input checks rather than manualsystems.
Allow sufficient time for collation and analysis of data if pinpoint accuracyis crucial.
Incorporate elements of probability within projections so that the requiredresponse to different future scenarios can be assessed.
Complete Include past data as a reference point for future projections.Include any planned developments, such as new products.
Information about future demand would be more useful than informationabout past demand.
Include external data.
Cost- Always bear in mind whether the benefit of having the information isbeneficial greater than the cost of obtaining it.
User-targeted Information should be summarised and presented together with relevantratios or percentages.
Relevant The purpose of the report should be defined. It may be trying to fulfil toomany purposes at once. Perhaps several shorter reports would be moreeffective.
Information should include exception reporting, where only those itemsthat are worthy of note - and the control actions taken by more juniormanagers to deal with them - are reported.
Authoritative Use reliable sources and experienced personnel.
If some figures are derived from other figures the method of derivationshould be explained.
Timely Information collection and analysis by production managers needs to bespeeded up considerably, probably by the introduction of betterinformation systems.
Easy-to-use Graphical presentation, allowing trends to be quickly assimilated andrelevant action decided upon.
Alternative methods of presentation should be considered, such as graphsor charts, to make it easier to review the information at a glance. Numericalinformation is sometimes best summarised in narrative form or vice versa.
A 'house style' for reports should be devised and adhered to by all. Thiswould cover such matters as number of decimal places to use, tableheadings and labels, paragraph numbering and so on.

BUSINESS STRATEGY AND INFORMATION SYSTEMS STRATEGY
The relationship between corporate, business and operational strategies is shown in thefollowing diagram.


STRATEGIES INVOLVING MANY FUNCTIONS (EG CHANGE MANAGEMENT,TOTAL QUALITY, RE-ENGINEERING)

Functional/operational strategies; information systems strategy
2.2 Information systems strategy is an example of a functional/operational strategy (althoughin some cases it may have strategic implications). Functional/operational strategies dealwith specialised areas of activity.
Functional area Comment
Information systems A firm's information systems are becoming increasingly important, as an item of expenditure, as administrative support and as a tool forcompetitive strength.
Marketing Devising products and services, pricing, promoting and distributing them, in order to satisfy customer needs at a profit.
Production Factory location, manufacturing techniques, outsourcing etc.
Finance Ensuring that the firm has enough financial resources to fund itsother strategies.
Human Secure personnel of the right skills in the right quantity at the rightresources time.
R&D New products and techniques.

Information systems and business strategy
2.3 It is widely accepted that an organisation's information system should support corporateand business strategy. In some circumstances an information system may have a greaterinfluence and actually help determine strategy. For example:
(a) IS/IT may provide a possible source of competitive advantage. This could involve newtechnology not yet available to others or simply using existing technology in a differentway.
(b) The information system may help in formulating business strategy by providinginformation from internal and external sources.
(c) Developments in IT may provide new channels for distributing and collectinginformation, and /or for conducting transactions eg the Internet.
Accountants and IT managers areseen as scorekeepers andadministrators rather than as abusiness partner during thestrategic planning process

Change from cost-orientated to Imarket-orientated ie development \of more effective strategic planningsystems


VISION AND REALITY
3.1 A company that has a vision of its own future, and some idea of how information
technology can be used to turn that vision into reality, may be able to use new technologiesfor strategic advantage.

3.2 One approach to creating a vision is to adopt a familiar three step approach, involvinganswering three questions about the organisation.

• Where are we now?
• Where do we want to be?
• How will we get there?

3.3 The first question can be answered using standard techniques such as a strengthsweaknesses, opportunities, threats (SWQT) analysis. This approach ensures that bothinternal and external factors are considered. We cover SWOT analysis in the context ofinformation systems development in Chapter 6.

3.4 Answering the second question requires vision. This does not have to be a continuation in
the organisation's current direction. It must be challenging, attainable and communicatedto those who will implement it.

3.5 Once this has been done, the strategy (in answer to the third question) can be defined.

3.6 A second approach takes the view that insiders are too tied to 'the way we do things now'and recommends the involvement of outsiders. An outsider may be able to more readilyanticipate dramatic shifts which might occur in the future. Additionally, an outsider doesnot have the insider's investment in maintaining the status quo.

Information systems, strategy and competitive advantage
3.7 It is now recognised that information can be used as a source of competitive advantage. Therealisation that information (and therefore information systems and informationtechnology) may be a source of competitive advantage and be key to achievingorganisational goals, has led to increased emphasis on the importance of formalmanagement strategies and plans for information and information systems.

3.8 A strategy is needed for areas in which decisions have the potential to have a major impacton an organisation. Many organisations have recognised the importance of information anddeveloped an information strategy, covering both IS and IT.

3.9 In commercial organisations it could be argued that one of the main aims of any strategy iscompetitive advantage - as success ultimately depends upon doing something better thancompetitors do. Business objectives, if achieved, should result in competitive advantage inone or more areas. This process is contributed to by ensuring the organisation's strategy forinformation and information systems is tied to business objectives.
(a) The corporate strategy is used to plan functional business plans which provideguidelines for information-based activities.
(b) On a year by year basis, the annual plan would try to tie in business plans withinformation systems projects, perhaps through a steering committee.

Information systems strategy
3.10 An IS strategy therefore deals with the integration of an organisation's informationrequirements and information systems planning with its long-term overall goals (customerservice etc). IS strategy is formulated at the level of business where specific customer needsetc can be delineated. It deals with what applications should be developed, and whereresources should be deployed.

3.11 The information technology (IT) strategy leads on from the IS strategy above. It dealswith the technologies of:
• Computing
• Communications
• Data
• Application systems

3.12 This provides a framework for the analysis and design of the technological infrastructureof an organisation. This strategy indicates how the information systems strategies that relyon technology will be implemented.
Why have an IS/IT strategy?

3.13 A strategy for information systems and information technology is justified on the groundsthat IS/IT:
• Involves high costs
• Is critical to the success of many organisations
• May be utilised as part of the commercial strategy in the battle for competitiveadvantage
• Can significantly change the business environment
• Affects all levels of management
• Affects the way management information is created and presented
• Requires effective management to obtain the maximum benefit
• Involves many stakeholders inside and outside the organisation

IS/IT is a high cost activity
3.14 Many organisations invest large amounts of money in IS, but not always wisely.

3.15 The unmanaged proliferation of IT is likely to lead to expensive mistakes. Two key benefitsof IT - the ability to share information and the avoidance of duplication - are likely to belost.

3.16 All IT expenditure should therefore require approval to ensure that it enhances rather thandetracts from the overall information management strategy.

IS/IT is critical to the success of many organisations
3.17 When developing an IS/IT strategy a firm should assess how important IT is in theprovision of products and services. The role that IT fills in an organisation will varydepending on the type of organisations. IS/IT could be:
• A support activity
• A key operational activity
• Potentially very important
• A strategic activity (without IT the firm could not function at all)
• A source of competitive advantage

IT can significantly change the business environment
3.18 IT is an enabling technology, and can produce dramatic changes in individual businessesand whole industries. For example, the deregulation of US airline system encouraged thegrowth of computerised seat-reservation systems (eg SABRE, as used by American Airlineswhich always displayed American Airlines flights preferentially). IT can be both a cause ofmajor changes in doing business and a response to them.

IT affects all levels of management
3.19 IT has become a routine a feature of office life, a facility for everyone to use. IT is nolonger used solely by specialist staff.

IT and its effect on management information
3.20 The use of IT has permitted the design of a range of Management Information Systems(MIS). Executive Information Systems (EIS), Decision Support Systems (DSS), and expertsystems can be used to enhance the flexibility and depth of MIS. (We look at different typesof information system in Chapter 2.)

3.21 IT has also had an effect on production processes. For example. Computer IntegratedManufacturing (CIM) changed the methods and cost profiles of many manufacturingprocesses. The techniques used to measure and record costs have also adapted to the use ofIT.

IT and stakeholders
3.22 Parties interested in an organisation's use of IT are as follows.
(a) Other business users - for example to facilitate Electronic Data Interchange (EDI).
(b) Governments - eg telecommunications regulation, regulation of electronic commerce.
(c) IT manufacturers looking for new markets and product development. User-groupsmay be able to influence software producers.
(d) Consumers - for example as reassurance that product quality is high, consumers mayalso be interested if information is provided via the Internet.
(e) Employees - as IT affects work practices.

3.25 An IS strategy therefore deals with the integration of an organisation's informationrequirements and information systems planning with its long-term overall goals (customerservice etc). IS strategy deals with what applications should be developed and whereresources should be deployed.

3.26 The information technology (IT) strategy leads on from the IS strategy above. It dealswith the technologies of:
• Computing
• Communications
• Data
• Application systems

3.27 This provides a framework for the analysis and design of the technological infrastructureof an organisation. This strategy indicates how the information systems strategies that relyon technology will be implemented.

Establishing organisational information requirements
3.28 The identification of organisational information needs and the information systemsframework to satisfy them is at the heart of a strategy for information systems andinformation technology.

3.29 The IS and IT strategies should complement the overall strategy for the organisation. Itfollows therefore that the IS/IT strategy should be considered whenever the organisationprepares other long-term strategies such as marketing or production.

Earl's three leg analysis
3.30 The writer Earl devised a method for the development of IS strategies. His methodidentified three legs of IS strategy development:
• Business led (top down emphasis, focuses on business plans and goals)
• Infrastructure led (bottom up emphasis, focuses on current systems)
• Mixed (inside out emphasis, focuses on IT/IS opportunities)

4 CRITICAL SUCCESS FACTORS
4.1 The use of critical success factors (CSFs) can help to determine the informationrequirements of an organisation. CSFs are operational goals. If operational goals areachieved the organisation should be successful.

4.2 The CSF approach is sometimes referred to as the strategic analysis approach. Thephilosophy behind this approach is that managers should focus on a small number ofobjectives, and information systems should be focussed on providing information to enablemanagers to monitor these objectives.

4.3 Two separate types of critical success factor can be identified. A monitoring CSF is used tokeep abreast of existing activities and operations. A building CSF helps to measure theprogress of new initiatives and is more likely to be relevant at senior executive level.
• Monitoring CSFs are important for maintaining business
• Building CSFs are important for expanding business

4.4 One approach to determining the factors which are critical to success in performing afunction or making a decision is as follows.
• List the organisation's objectives and goals
• Determine which factors are critical for accomplishing the objectives
• Determine a small number of key performance indicators for each factor

4.5 The determination of key performance indicators for each of these CSFs is not necessarilystraightforward. Some measures might use factual, verifiable data, while others might makeuse of'softer' concepts, such as opinions, perceptions and hunches.

4.6 For example, the reliability of stock records can be measured by means of physical stockcounts, either at discrete intervals or on a rolling basis. Forecasting of demand variationswill be much harder to measure.

4.7 Where measures use quantitative data, performance can be measured in a number of ways.
• In physical quantities, for example units produced or units sold
• In money terms, for example profit, cevenues, costs or variances
• In ratios and percentages

4.8 In general terms Rockart identifies four sources of CSFs.
(a) The industry that the business is in.
(b) The company itself and its situation within the industry.
(c) The environment, for example consumer trends, the economy, and political factors ofthe country in which the company operates.
(d) Temporal organisational factors, which are areas of corporate activity which arecausing concern, for example, high stock levels.

4.9 More specifically, possible internal and external data sources for CSFs include thefollowing.
(a) The existing system. The existing system can be used to generate reports showingfailures to meet CSFs.
(b) Customer service department. This department will maintain details of complaints,refunds and queries.
(c) Customers. A survey of customers, provided that it is properly designed andintroduced, would reveal (or confirm) those areas where satisfaction is high or low.
(d) Competitors. Competitors' operations, pricing structures and publicity should beclosely monitored.
(e) Accounting system. The profitability of various aspects of the operation would be akey factor in any review ofCSFs.
(f) Consultants. A specialist consultancy might be able to perform a detailed review of theorganisation to identify CSFs.

4.11 EXAMPLE
An organisation has an objective to maintain a high level of service direct from stockwithout holding uneconomic stock levels. This is quantified in the form of a goal, whichmight be to ensure that 95% of orders for goods can be satisfied directly from stock, whileminimising total stockholding costs and stock levels. CSFs and KPIs might then beidentified as the following.
CSF KPI
Supplier performance Average order lead time
Stock records reliability Number of discrepancies found
Accurate demand forecasting Difference between forecast and actual demand
CSF approach: strengths and weaknesses4.12
CSF approach - strengths Comment
Takes into accountenvironmental changes
The CSF approach requires managers to examine theenvironment and consider how it influences theirinformation requirements.
Focuses on information
The approach doesn't just aim to establish organisationalobjectives. It also looks at the information and informationsystems required to establish and monitor progress towardsthese objectives.
Facilitates top managementparticipation in systemdevelopment
The clear link between information requirements andindividual and organisational objectives encourages topmanagement involvement in system (DSS, EIS) design.

4.13
CSF approach - weaknesses Comment
Aggregation of individualCSFs
Wide-ranging individual CSFs need to be aggregated into aclear organisational plan. This process relies heavily onjudgement. Managers who feel their input has beenneglected may be alienated.
Bias towards topmanagement
CSFs change often
When gathering information to establish CSFs it is usuallytop management who are interviewed. These managersmay lack knowledge of operational activities.
The business environment, managers and informationsystems technology are subject to constant change. CSFsand systems must be updated to account for change.


Chapter roundup Summary
• Organisations require information for a variety of purposes including
· Planning
· Controlling
· Recording transactions
· Measuring performance
· Decision making
• A strategy is a general statement of long-term objectives and goals and the ways by whichthese will be achieved. Strategic planning is the formulation, evaluation and selection ofstrategies for the purpose of preparing a long-term plan of action to attain objectives.
• Information systems and Information Technology (IS/IT) strategy refers to the long-term planconcerned with exploiting IS and IT either to support business strategies or create newstrategic options.
• IS/IT strategy is an example of a functional/operational strategy, but may have strategicimplications.
• A strategy is needed for IS/IT because these areas involve high costs, are critical to thesuccess of many organisations, can be used as a strategic weapon and affects internal andexternal stakeholders.
• IS/IT are sufficiently important and widespread to require proper planning and managementattention.
• IT developments have increased the amount of information available to organisations. It isimportant to ensure information is useful - that it is of good quality.
• Developing strategy involves taking a number of steps, from setting strategic objectives rightthrough to evaluating actual performance. Three basic issues are the organisation's overallbusiness objectives and in consequence its IS/IT needs, the organisation's current ITusage and the potential opportunities that IT can bring.
• Critical success factors are a small number of key operational goods vital to the success ofan organisation.