Itm Lecture 6

INFORMATICS Information Technology Management

Lecture 6

16th January 2008 ITM Lecture 6 Advanced Diploma (Thames College)

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Information o at o Tec Technology o ogy Management a age e t

Unit 15: Decision Support S System andd Executive E i Information System

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Decision ec s o Support Suppo t System Syste (DSS) ( SS)

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What is a Decision Support pp System? y z

z

z z

An organized collection of people people, procedures procedures, software, database, and devices used to support problem-specific bl ifi ddecision i i making ki An interactive, highly "user-friendly" system that supports management decisions that are semip in advance structured or that cannot be specified Focus on decision-making effectiveness Off the Offers th potential t ti l to t generate t higher hi h profits, fit lower costs and better products and services ITM Lecture 6 Advanced Diploma (Thames College)

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DSS SS & Decision ec s o Making a g Level eve z z z

Decision Support System, System though skewed towards top level management, are used at all levels M Managers at allll llevels l fface unstructured d ddecisions ii Quantity and magnitude of unstructured decisions increases with management level

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Components Co po e ts of o DSS SS zA

D Decision i i SSupportt System S t is i composedd g of the following: z User

Interface z Data D M Management z Model Management g

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Components of DSS – U r Int User Interface rf z Users U

iinteract t t with ith a DSS through th h the th user interface. z It is important therefore that user i interfaces f are easy to learn l andd to use. z The method of interfacing may vary with each DSS.

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Components of DSS – D t Management Data M n m nt zA

ttypical i l DSS will ill access more than th one database. These mayy contain both internal and external data. z Data D iis extractedd from f these h databases d b and d updated p into a DSS database.

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Components of DSS – M d lM Model Management n m nt z The Th

Model M d lM Managementt subsystem b t contains the model base. z Models are software programs that support the h user iin a particular i l ddecision ii makingg situation.

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Business us ess Applications pp cat o s z

Financial Investment z

z

z

Some investment banks and brokerage firms use DSS in taking market positions with their own assets. assets The decision-making support comes in the form of the software'ss ability to identify trends or disturbances in the software market prices of securities and options.

Ship Loading and Unloading z

DSS can be used to load and unload ships in an optimal s o . Thiss iss important po ass a sship p cou could d be ppicking c g up fashion. and dropping off cargo at many different ports. ITM Lecture 6 Advanced Diploma (Thames College)

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Benefits e e ts z Fast F t

Response R to t p Unexpected Situations z New N IInsights i h and d Learningg z Cost Savings

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Benefits e e ts (1) ( ) z Fast F t

Response R to t Unexpected U t d Situations Sit ti

zA

DSS enables a thorough, quantitative analysis in a short time. z This results in the user being b able b to p changes g in business situations handle rapid without waiting for the IT department to perform programming changes as would be the case in an IRS. ITM Lecture 6 Advanced Diploma (Thames College)

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Benefits e e ts (2) ( ) z New N

Insights I i ht andd Learning L i

z The

user can be exposed to new insights throughout the composition of the model andd an extensive t i sensitivity iti it "what-is" " h ti" analysis. z The new insights can help in training inexperienced managers and other employees as well. ITM Lecture 6 Advanced Diploma (Thames College)

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Benefits e e ts (3) z Cost C t

Savings S i

z Routine

applications of a DSS may result in consideration cost reduction, or in r d i th reducing the costt off wrong r ddecisions. ii

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Group p Decision Support pp System y ((GDSS)) Group Decision Support System (GDSS) is a decision support system which provides support for problem formulation and g p or teams of people p p solution and decision makingg byy groups z GDSS is designed to support effective group communication and good decision making techniques, as well as creative thinking. z

z

GDSS software must be especially user friendly, since often groups have less patience with bad software ft than th do d individuals. ITM Lecture 6 Advanced Diploma (Thames College)

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Components Co po e ts of o tthee GDSS G SS z There Th

are five fi components t in i GDSS

z Hardware z Software z People P l z Data z Procedures

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Characteristics C a acte st cs of o a GDSS G SS z

Decision making support Decision-making z

z z

z

z

Reduction of negative group behavior z

z

Delphi approach: Decision makers are scattered around the globe Brainstorming: Say things as you think (think out loud) Group consensus approach: The group reaches a unanimous decision (everybody agrees) Nominal group technique: Voting A ttrained i d meeting ti facilitator f ilit t to t help h lp with ith sidetracking id t ki

Automated record keeping ITM Lecture 6 Advanced Diploma (Thames College)

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Examples a p es of o G GDSS SS So Software twa e z Lotus L t

Notes N t

z Store,,

manipulate, p , distribute memos

z Microsoft

Exchange

z Keep

individual schedules z Decide on meeting times

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Executive Information System y (EIS) ( )

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Executive ecut ve Information o at o Systems Syste s z

An Executive Information Systems (EIS) is a system that serves the information needs of top executives by providing rapid access to timely information with "drill-down" capabilities. biliti z It is intended that the senior executive has the latest details about the company company'ss key performance indicators as well as economic and industrial indicators. z These are information that a top executive requires to monitor the health of a large organization. z The information presented through an EIS come from both internal and databases and external sources like the online Dow Jones News Retrieval service. ITM Lecture 6 Advanced Diploma (Thames College)

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Executive ecut ve Problem P ob e Analysis a ys s z z z

z z

Havingg identified a significant g variance, the executive needs to view the data from a number of different perspectives. It is not enough g to know that an unfavorable profit p variance of 10% has occurred in one of the subsidiaries. Some divisions within that subsidiaryy mayy have increased profits while other divisions have deviations of more than 10%. An EIS can support multiple levels of investigation. Byy selectingg the highlighted g g variance on the screen,, it is possible to obtain more details of causes, "drilling-down" to gget lower levels of details. ITM Lecture 6 Advanced Diploma (Thames College)

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Information o at o Tec Technology o ogy Management a age e t

Unit 16: Strategic g Role of Information Systems y

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Relevance of Information to M n m nt D Management Decisions ii n z

z

z

Managers are not able to directly observe all aspects of operations and therefore depend on information i the in h fform off reports to help h l them. h Management are faced by an accelerating rate of change, an ever more complex environment and at g levels,, byy considerable uncertainty. y higher It is difficulty to produce relevant information but ironically it is even more important to managers ironically, today. ITM Lecture 6 Advanced Diploma (Thames College)

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What W at iss an a MIS? S? z To T

convert n rt ddata t from fr m int internal rn l & external t rn l sources into information z To communicate this information to managers z To enable them to make timely and effective decisions z Emphasis on the use se of information, information not on how it is produced. ITM Lecture 6 Advanced Diploma (Thames College)

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Definition e t o of o MIS? S? z

The definition of a Management Information System is: z

A system to convert data from internal and external sources into information and to communicate this information, in an appropriate form, to managers at all levels in all functions to enable them to make timely and effective decisions for planning, directing and controlling the activities for which they are responsible. ITM Lecture 6 Advanced Diploma (Thames College)

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MISS and a d IT T z

z z

An MIS in today today'ss context is usually a mixture, mixture with the computer being used for storage and processing of data, while the human processes come into play when judgment is called for, or when an unusual situation arises. arises Information technology is not essential to an MIS but it can be b very useful. f l At higher levels of management, there is a greater amount of unstructured problems and decisions where human involvement is essential. ITM Lecture 6 Advanced Diploma (Thames College)

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Management a age e t Levels eve s z

Management is often divided into three levels based on the type of management activity performed. z Strategic Management z Tactical T ti l Management z Operationall Management

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Strategic St ateg c Management a age e t z Strategic St t i

managementt deals d l with ith long l range considerations. z Decisions to be made deal with the choice off business b i di direction, i market k strategy, product mix,, etc. p

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Tactical Tact ca Management a age e t z Tactical T ti l

managementt has h a medium di term t p planning g horizon. z It I includes i l d acquisition i i i and d organization i i off resources,, structuringg of work,, and recruiting and training of personnel personnel. ITM Lecture 6 Advanced Diploma (Thames College)

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Operational Ope at o a Management a age e t z Operational O ti l

managementt is i related l t d to t short h t p term decisions for current operations. z Pricing, production levels, inventory levels, etc, are the h result l off operational i l planning l i and control.

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MISS for o Ope Operational at o a Management a age e t z At

the th operational ti l managementt level, l l the th p main concern is with the implementation and control of the day-to-day activities of the organization. organization z Operational p management g require q their MIS to provide them detailed control information about transactions transactions. ITM Lecture 6 Advanced Diploma (Thames College)

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MISS for o Tact Tactical ca Management a age e t Tactical level management implement strategic objectives and monitor operations. z Unlike MIS at the operational level level, there is no best design for tactical level MIS. z In many cases, cases the MIS for tactical management is part of a transaction processing system. z Control systems with information feedback are essential to carry out the monitoring role and it is this level which administers most of the well known conventional control systems such as budgetary control, production control, inventoryy control and so on. z

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MISS for o St Strategic ateg c Management a age e t z z

z

Strategic planning and decision making involves setting a long term direction for the company. Strategic management needs to understand the environment and predict key trends and challenges facing the organization in the future. There is a need for MIS to obtain information about the environment by a scanning and information gathering process in order to identify potential threats and opportunities. ITM Lecture 6 Advanced Diploma (Thames College)

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Problems P ob e s with w t MISS z

MIS cannot provide management with the information they need due to the following reasons: z z z z z z

Lack of Management Direction Lack of management knowledge of computers Lack of topp management g support pp Lack of management participation in MIS design Management do not always know what information they need IT personnel often do not know enough about management to produce relevant information for the managers they serve ITM Lecture 6 Advanced Diploma (Thames College)

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Strategic g Role of Information Systems y z Information

ssystems stems are no longer restricted to backroom support roles. z Organizations are increasingly aware of the potential i l strategic i applications li i off y information systems.

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Competitive Co pet t ve Forces Fo ces z

z

Michael Porter discussed 5 organization organization-level level competitive forces in an industry which together determine how strong an organization is in its industry. These forces are: z z z z z

Bargaining Power of Suppliers Bargaining Power of Buyers Threats of New Entrants Threats of Substitution Intensity of Rivalry ITM Lecture 6 Advanced Diploma (Thames College)

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Bargaining a ga g Powe Power of o Suppliers Supp e s z

z

z

The bargaining power of suppliers is high if there are concentrated sources of supply and few substitutes. substitutes If these near monopoly situations, the suppliers can push prices upward and can be indifferent about service or quality. Information Technology can be used to reduce supplier power by developing in in-house house capability to produce or service or buying into a supplier. ITM Lecture 6 Advanced Diploma (Thames College)

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Bargaining a ga g Powe Power of o Buyers uye s z When

buyer is high (e (e.g. g when the buyer is large and/or the products are undifferentiated), then there is downward pressure on prices and upward pressure on both product quality and service. z Information Technology can be used to reduce buyer power such as increasing switching costs. ITM Lecture 6 Advanced Diploma (Thames College)

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Threats T eats of o New Entrants t a ts z

z

z

When an industry experiences good profit margins, margins it is attractive for new entrants to join the industry and this will create downward pressure on prices due to the increased availability of products and service. An existing player in the market can create can entry barrier by using IT to make the cost too high for any new player. player A new entrant can use IT to improve its services or product d andd thereby, h b overcome b barriers i set up b by existing players. ITM Lecture 6 Advanced Diploma (Thames College)

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Threats T eats of o Substitution Subst tut o z Substitution

of products and services can reduce or eliminate the market for existing organizations and thereby weaken it. z A late entrant to the market may choose to introduce a product that is a technological advancement over the existing products in the market, market and thereby weaken existing players by the threat of substitution. ITM Lecture 6 Advanced Diploma (Thames College)

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Intensity te s ty of o Rivalry va y The intensity of rivalry in the market affects the overall profitability, and it is usually greater in mature t or declining d li i markets. k t z Price wars usually y benefit the consumer and eliminate some of the weaker players in the market. market z IT can be used to overcome the dilemma of h i to llower prices having i while hil iincreasing i llevels l off service. z

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Competitive Co pet t ve Strategy St ategy z

z

Firms have discovered many different approaches and the best strategy for a given firm is ultimately a unique combination reflecting its particular circumstances. At the broadest level we can identify three internally consistent generic strategies for creating such a defendable position in the long and outperforming competitors tit in i an industry: i d t z z z

Overall Cost Leadership Diff Differentiation ti ti Focus ITM Lecture 6 Advanced Diploma (Thames College)

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Competitive Strategy – O r ll C Overall Costt L Leadership d r hip Cost leadership exists when a company can provide an "identical" product or service at the lowest cost in that industry. y z Cost leadership requires aggressive construction of efficient - scale facilities,, vigorous g pursuit p of cost reductions from experience, tight cost and overhead control, avoidance of marginal customer accounts, and cost minimization in areas like R&D service, sales force, advertising, and so on. z A great deal of managerial attention to cost control is necessary to achieve these aims. z

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Competitive Strategy Diff r nti ti n Differentiation z An

organization may choose to provide a differentiated Unique product or service at a premium price in that industry. z The aim in differentiating the product or service offering of the term is to create something that is perceived industry-wide as being unique. unique ITM Lecture 6 Advanced Diploma (Thames College)

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Competitive Co pet t ve Strategy St ategy - Focus z

Focus ocus itss pproduct oduc or o service se v ce pprovision ov s o oon a pparticular cu buye buyer group, segment of the product line, or geographic market for an identified market segment, by either cost leadership or differentiation. z The entire focus strategy is built around serving a particular target very well, ll andd eachh functional f i l policy li is i developed d l d with ih this in mind. z Able to serve its narrow strategic target more effectively or efficiently than competitors who are competing more broadly. z Achieves either differentiation from better meeting the needs of the particular target, or lower costs in serving this target, or both. ITM Lecture 6 Advanced Diploma (Thames College)

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Information o at o Tec Technology o ogy Management a age e t

Unit 17: Prototyping and Feasibility Study

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Prototyping and Feasibility Study

Prototyping

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Problems P ob e s with w t Classical C ass ca SDLC S C z User

Requirements Change z Incomplete p User Requirements q z Development Targets are Missed

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Problems with Classical SDLC U rR User Requirements q ir m nt Ch Change n z z z z

Systems often take years to analyze, analyze design, design and implement. During development period, period the environment and user needs is are constantly changing. Th finished The fi i h d system might i h not meet the h new applications environment. With the traditional SLDC approach, it is relatively difficult to respond to new needs once users have signed off on the requirements analysis and the design. ITM Lecture 6 Advanced Diploma (Thames College)

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Problems with Classical SDLC In mpl t U Incomplete Userr R Requirements q ir m nt z z z z

People often cannot articulate what type of information they really need in their work. With the traditional SDLC approach, approach users do not really see the new system until it is installed. M Many users h have a diffi difficult l time i visualizing i li i the h system by looking at a set of diagrams or specifications. Requirements analysis had to be repeated because additional requirements were discovered or because users changed their minds. ITM Lecture 6 Advanced Diploma (Thames College)

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Problems with Classical SDLC D l pm nt Targets Development T r t are r Missed Mi d z z z z z

Systems developers are often notoriously optimistic. Deadlines are set and missed; then re-set and often missed again. The systems usually require more resources than originally estimated and costs frequently climb over budget. budget Problems of miscommunication, omissions, and human error complicate matters matters. Projects are often cancelled as cost begin to exceed benefits and the probability of ever finishing them within a reasonable span of time becomes more and more remote. ITM Lecture 6 Advanced Diploma (Thames College)

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P ototyp g Prototyping z The

process of building an experimental system quickly and inexpensively for demonstration and evaluation so that users can better determine information requirements. z By interacting with the prototype, users can get a better idea of their information requirements ITM Lecture 6 Advanced Diploma (Thames College)

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Thee Prototyping T P ototyp g Process P ocess z

Phase 1: z

z

Phase 2: z

z

Creatingg the Prototype yp System. y

Phase 3: z

z

Define System Specifications.

Refine fi the h Prototype System. S

Phase 4: z

Develop Operational System. ITM Lecture 6 Advanced Diploma (Thames College)

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Phase 1: D fin SSystem Define t m Specifications Sp ifi ti n z One

of the rough spots in the prepre specification approach to systems development has been the definition of system specifications. specifications

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Phase 2: Cr tin th Creating the Pr Prototype t t p System S t m z Project

team members rough out the logic of the system and how the elements fit together and then work with the user to define the I/O interfaces. interfaces

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Phase 3: R fin the Refine th Prototype Pr t t p System S t m z Users

sit down at a terminal or PC and evaluate portions and eventually all of the prototype system. z The system is then expanded and refined to meet the users' total information needs.

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Phase 4: D l p Op Develop Operational r ti n l SSystem t m z The

prototype system is custom coded. coded

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System Prototyping Syste P ototyp g Prototyping involves a repetitive sequence of analysis, design, modeling and testing. z The end product of System Prototyping is a full-featured, workingg model of the information system, ready for implementation. z

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Design es g Prototyping P ototyp g z z

Design Prototyping is used to verify user requirements. Th endd product The d off Design D i P Prototyping i is i a userapproved design prototype that documents and benchmarks the features of the finished system.

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Advantages dva tages of o Prototyping P ototyp g Most useful when there is uncertainty about requirements or design solutions. z Valuable for the design of End-user interface of y an Information System. z Prototyping encourages intense end-user involvement throughout the systems development lifecycle. z It is more likely to produce systems that fulfill user requirements. q z

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Disadvantages sadva tages of o P Prototyping ototyp g z The

rapid pace of development can create quality problems, which are not discovered untill the h ffinished h d system is operational.l z Other system requirements, requirements such as reliability and maintainability, cannot adequately be testedd using i a prototype. z In very y complex p systems, y , the prototype p yp becomes unwieldy and difficult to manage ITM Lecture 6 Advanced Diploma (Thames College)

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Prototyping and Feasibility Study

Feasibility Study

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What W at iss a Feasibility Feas b ty Study? z

z z

z

The Feasibility Study is one of the steps within the Preliminary Investigation Phase of the Systems Development Life Cycle (SLDC). The analyst learns from the user what is expected of the proposed information system. system The analyst uses technical skills and knowledge to d id on various decide i alternatives l i to be b considered id d ffor implementation. The feasibility study has to contain enough detail so that an alternative can be selected for development. ITM Lecture 6 Advanced Diploma (Thames College)

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Types of o Feasibility Feas b ty z z

Different types of feasibility that must be evaluated in order to determine if the project is worth doing. A ffeasibility ibili study d uses three h major j yardsticks d i k to measure, or predict a system's success: z z z

Economic Feasibility Technical Feasibility Operational Feasibility

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Operational Ope at o a Feas Feasibility b ty zA

system that has operational feasibility is one that will be used effectively after it has been developed.

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Technical Tec ca Feasibility Feas b ty z

z

A systems request has technical feasibility if the organization has the resources to develop or purchase install, purchase, install and operate the system. system Project risk can be assessed based upon: z z z

z

Project size Project structure Development group's experience with the application pp User group's experience with development projects p j and the application pp area ITM Lecture 6 Advanced Diploma (Thames College)

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Economic co o c Feasibility Feas b ty A systems request has economic feasibility if the projected benefits of the proposed system outweigh the estimated costs involved in acquiring, q g installing, g and operating p g it. z Before management will approve any large computer system, y , an appraisal pp of the benefits and costs of the system y must be done. z Essentially y what happens pp is that all costs associated with the proposed systems project is calculated, as well as the benefits to be derived from this system. z Then we use certain financial methods to rank projects. z

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What W at iss Costs? z

Among the cost items that are taken into consideration are h d hardware, software, f personnel, l andd establishment bli h off new procedures and representations of data. z Cost is divided into several types: z

Tangible Costs (can easily be measured in dollars) z

z

Intangible Costs (cannot be easily measured in dollars) z

z

Examples: loss of customer goodwill, loss of employee morale

One-Time Costs (project startup, initiation and development) z

z

Example: Hardware

E Example: l System S t Development, D l t Data D t Conversion C i

Recurring Costs (ongoing use of the system) z

Example: Software Maintenance ITM Lecture 6 Advanced Diploma (Thames College)

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What W at iss Benefits? e e ts? z

T e benefits The be e ts are a e divided d v ded into to Tangible g Benefits and Intangible Benefits. z

Tangible Benefits are those that can be measured easily (most readily translated into dollars). z

z

Examples: Cost reduction, reduction Opening new markets and increasing sales opportunities

Intangible Benefits are those that cannot be measured easily (difficult to quantify) z

Examples: Increased employee morale, morale Promotion of organizational learning and understanding ITM Lecture 6 Advanced Diploma (Thames College)

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What W at iss Requirement? equ e e t? zA

Requirement is a feature that users identify as being necessary or useful in a system. z How are requirements determined? The business must first be understood. understood z The problems are studied and opportunities for improvement are identified. z It is these opportunities pp that are eventuallyy turned into statements of requirements. z

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Importance po ta ce of o Requirements equ e e ts z z z z z

The requirements stage is one of the early stages in SDLC. By studying both the existing and proposed systems in detail, various problems can be anticipated. I is It i iimportant to consider id h how these h problems bl can b be solved or at least, how to minimize their impact. It is important that requirements are clear and complete. Subtle misunderstandings g mayy result in defects which could be hard to detect. ITM Lecture 6 Advanced Diploma (Thames College)

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Methods et ods of o Data ata Collection Co ect o z Primary

data collection involves direct interaction with the source of the data. z Interview z Observation Obser ation z Questionnaire z Documents

Review

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Interview te v ew z z z z

z

The systems analyst spends a great deal of time interacting with others, particular in interviews settings. Interviews have varying degrees of structure; for a first meeting there may be no structure at all. As the project progresses, progresses more structured interviews are conducted. The analyst may wish to prepare in advance an interview schedule containing the questions to be asked and the pints to be covered. This will ensure that no pint is omitted or that the interview drifts from its original objectives. ITM Lecture 6 Advanced Diploma (Thames College)

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Obse vat o Observation z One

technique for collecting data on a process is to observe that process. z Frequently in systems analysis and design we will ill Walkthrough Walkthro gh system s st m observing bs r in crucial information flows and decision points.

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Quest o a e Questionnaire A questionnaire allows us to collect data from a relatively large number of people at a reasonable cost. zAq questionnaire can be thought g of as a structured interview form with questions designed so that they can be answered without face-to-face encounter. z Designing a good questionnaire is a difficult task. z

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Documents ocu e ts Review ev ew Some types of information may be obtained from reviewing existing company records or documents. z The existing g work procedures p or company p y policy may be reviewed to obtain information about the current business processes. processes z An examination may be made of company records concerning the volume of invoices or p to determine p problem areas. shipment z

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Problems of Conventional Flowcharts z Lack

of discipline or structure. z Very few guidelines on nh how tto ddevelop l p flowcharts z Flowcharts for complex l systems are often unreadable. ITM Lecture 6 Advanced Diploma (Thames College)

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Data ata F Flow ow Diagrams ag a s (DFD) ( F ) z

A Data Flow Diagram (DFD) is a graphical tool to depict the flow of data through a system and the h workk or processing i performed f d by b that h system. It shows how data moves through an information system y but does not show program p g logic or processing steps. z It only represent a logical model that shows what the system does, not how it does it. z

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Data ata F Flow ow Diagrams ag a s z

Data Flow Diagrams g (DFD) ( ) require q onlyy four symbols, y , making them very easy to create. z

z z z

z

Open-ended rectangles represent store of data, such as a file of items in inventory, inventory their quantity quantity, and the Economic Recorder Quantity ( EOQ). Circles stand for some type of processing, and arrows represent the flow of data. data A square is a source or destination of data. Dataflow diagrams should also be prepared in a topdown manner.

The context diagram is a summary diagram of the first level DFD and serves to put the system under study in its context within the business environment. ITM Lecture 6 Advanced Diploma (Thames College)

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DFD F Symbols/Elements Sy bo s/ e e ts

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Data ata F Flow ow Diagrams ag a s (DFD) ( F ) z Tool

that graphically shows flow of data in system

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Decomposition p of Context Diagram g

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Context Co te t Diagrams ag a s

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Level eve 1 Diagrams ag a s

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Entity-Relationship y p Diagram g (ERD) ( ) z Tool

that graphically shows connections between entities in system

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Entity t ty Diagrams ag a s z z z z

z z

An entityy is an item of interest to the organization g like a department, staff, machines, customers, etc. An entity diagram shows the relationships between such it ms off interest. items int r st Take the example of a department and its staff, both of which are entities. The relationship between these entities can be shown by drawing a diagram linking them together. We could also show h a particular i l ki kindd off relationship l i hi like lik one to many. The entity diagram can be used to understand and communicate the relationships between entities. The data fields (attributes) associated with each entity may also be documented. ITM Lecture 6 Advanced Diploma (Thames College)

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Information o at o Tec Technology o ogy Management a age e t

Unit 18: Systems I l Implementation i and d Development Tools

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Systems Implementation and Development Tools

C Conversion i

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Conversion Co ve s o Tasks Tas s To ensure a smooth and successful implementation, users must be familiar with the features of the system, operators must know how to make the system function properly, and the conversion itself must go off smoothly. z Conversion includes the creation of all required files and d b database, establishing bli hi a b backup k copies, i and d converting i tested d programs to operating status. z Data D t conversion i is i a central t l partt off a system t conversion i regardless whether the preceding system was manual or computer based. computer-based. z The data conversion must be carefully planned and also crossg checked to see that it is done right. z

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Data ata Co Conversion ve s o Methods et ods z There

are fours strategies, strategies the choice of which is dictated by the given situation z Parallel

Systems z Direct Cutover C to er z Pilot System z Phase-in of System

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Data Conversion Methods – P r ll l SSystems Parallel t m A safe and conservative conversion approach z Running both old and new systems for a period of time z The output p of the new system y is compared p closelyy with the output of the old system and any difference reconciled z When users are comfortable that the new system i working is ki properly, l the h old ld system iis eliminated li i d z Very y expensive, p , additional staff is required. q z

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Data Conversion Methods – Dir t C Direct Cutover t r This method of conversion require much more careful and detailed planning than the other alternatives. alternatives z A risky conversion approach in which the new system completely l l replaces l the h old ld one on an appointed i d dday. z Involves stopping the old system and starting the new system on a specific date. z High g potential p for p problems and errors. Less costlyy if no problem, otherwise more costly. z

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Data Conversion Methods – Pil t System Pilot S t m z Involves

running the new system for one group of uses rather than all users z When the pilot system runs without pr bl ms th problems then n it is rrolled ll d outt tto the th other th r users

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Data Conversion Methods Ph in off SSystem Phase-in t m z z

z

z

Piecemeal approach Components of the new system are slowly phased in while components of the old system are slowly phased out All Allows the h organization i i to b being i taking ki advantage d off the newly developed support tools while retaining fl ibili to cope with flexibility i h any deficiencies d fi i i When everyone is confident that the new system is performing as expected, then the old system is completely phased out ITM Lecture 6 Advanced Diploma (Thames College)

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Systems Implementation and Development Tools

T i i Training

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Classroom C ass oo T Training a g z Classroom

training involves a live instructor conducting training for students.

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Advantages dva tages z

Classroom training has several strong advantages over other forms of training, which do not use live instructors. instructors z z

z

z

Feedback is immediate when the problems occur. Both the Learners and the teachers can ask questions to gauge the group's understanding. The teaching can be tailored to the learners by adding company-specific examples or job-specific examples. The classroom is a familiar and acceptable p environment for most people.

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Disadvantages sadva tages z

On the negative side, side classroom instruction also has a number of strong disadvantages. z

z

z

z

It is i usually ll more expensive i than th mediated di t d training without instructors. Training facilities are expensive, expensive particular, particular if hands-on hands on computer training is to be done. Users have to wait until a class starts to get the training they need. Teaching quality can vary considerably from course to course.

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Internal te a vs. External te a Training Ta g z If

the th company decides d id to t sponsor training, t i i the next step p is to decide whether to do it internally or whether to contract the training out to external vendors. vendors

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Advantages dva tages of o Internal te a Training Ta g z Many M

fi firms use iinternal t l training t i i because b it has several important advantages. There is greater control over quality. If there are quality problems, these can be overcome. With external training, there is less control over quality. quality z Courses can be tailored to the corporation by i l di company-specific including ifi information. i f i z

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Advantages dva tages of o External te a Training Ta g z

External vendors offer a number of advantages over internal training. z

z z

If internal training is done in geographically decentralized organizations, the use of external vendors can provide cheaper local training when popular application software packages or the basic use of the computer are to be taught. Unless a firm has a very large training program, external training will be less expensive. For popular software packages or basic machine use, externall vendors d will ill offer ff courses almost l continuously, i l whereas internal programs may offer these course less frequently. ITM Lecture 6 Advanced Diploma (Thames College)

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Su Summary ay

Systems Implementation and Development Tools

D l Development T Tools l

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Development eve op e t Tools Too s Computer Aided Software Engineering (CASE) is the use of computer technology to help improve application systemss development. syste deve op e t. z The earliest CASE tools were used to create flowcharts and data flow diagrams. z Later versions of CASE allowed computer professionals to create complete and detailed specifications and to later generate structured program code. z The CASE software can then generate a detailed documentation package for easy maintenance. z

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Features Featu es of o CASE C S z CASE

consists of a set of workstation workstationbased software tools designed to support application developers developers. z The activities that most CASE tools include are described below. z Draw

Descriptive Diagrams z Maintain Data Dictionary z Design Display Screens z Design Output Layouts ITM Lecture 6 Advanced Diploma (Thames College)

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Features of CASE – Dr D Draw Descriptive ripti Di Diagrams r m z Diagramming Di i

tools l provide id the h ddeveloper l with the abilityy to draw various types yp of diagrams like data flow diagram, flowcharts, etc. t

z Making

modifications to diagrams is much faster with this tool. ITM Lecture 6 Advanced Diploma (Thames College)

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Features of CASE – M int in D Maintain Data t Dictionary Di ti n r z This Thi

iis used d to store and d validate lid definitions of data items used in the system. y

z It

also records the programs or tables where each data item is used. used

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Features of CASE – D i n Di Design Display pl SScreens r n z CASE

iis used d to quickly i kl create screen designs g and to generate g the code based on this design. z These can be b reused d in other applications. z Screen intensity, intensity use of reverse letters and inclusion of underlining are all easily specified. ITM Lecture 6 Advanced Diploma (Thames College)

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Features of CASE – D i nO Design Output tp t Layouts L t z As A

with i h screen ddesigns, i CASE tools l can also be used to design g report p layouts. y

z Consistency

between reports can be achieved by starting with one standard template.

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Benefits e e ts of o CASE C S z What

are the benefits of using CASE?

z Development

time is shortened z Development standards can be enforced. z Data Dictionary y is automaticallyy produced p

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Benefits of CASE – D l pm nt Time Development Tim iis Sh Shortened rt n d z With

automated tools tools, the effort required to complete each task is lessened. z For F

example, l instead i d off drawing d i data d flow fl diagrams by hand, it can be done with CASE.

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Benefits of CASE – Development Standards can be Enforced z Standards

define the rules for certain development decisions. z Having these h standards d d embedded b dd d in software ensures it is more consistently performed. z For

example, p , an organization g mayy have standards regarding the naming convention of data fields or the diagramming method.

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Benefits of CASE – Data Dictionary is Automatically Produced z There

is no need to review the entire system to ensure that the data dictionary is complete mpl t and nd consistent n i t nt if each h ddata t field fi ld is i defined in the data dictionary at its point of creation. ti

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Limitations tat o s of o CASE C S z Does

not support the full SDLC

z CASE

software is not able to support the full d l development lif life cycle. l z The design to code transformation is not fully automated, d andd results l in i much h analyst l and d the programmer effort anyway.

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Documentation ocu e tat o z There

are two types of documentation

z User

Documentation z Operations Documentation

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User Documentation Use ocu e tat o z z

z z

The first type of documentation is the User Manual, Manual also known as the User Guide. The user manual contains screen and report p layouts, y , with explanation of how to use a transaction, or read a report. I also It l h has other h ffeatures lik like a lilist off error conditions di i and how to correct error. The user manual should be referred to by the user who has a question or a problem about the system before he or she refers to the IT p person supporting pp g the application. ITM Lecture 6 Advanced Diploma (Thames College)

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Operations Ope at o s Documentation ocu e tat o z z z

z

z

The operations section of an IT department has to operate the system after it has been implemented. This ggroup p needs information on normal operating p g procedures and on how to respond to errors. The Operations Manual will contain information about starting i and d shutting h i ddown the h system, plus l ddetails il about how to run the batch jobs. For each batch job job, a complete systems flowchart that shows the input required, the files necessary, and any printed output p p must be documented. It is important for operators to know possible error conditions and how to respond to them. ITM Lecture 6 Advanced Diploma (Thames College)

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Importance po ta ce of o Documentation ocu e tat o z This

particularly so if there is a deadline approaching and if the tasks are behind schedule. schedule z Documentation must be treated as part of the h complete l package k off deliverables. d li bl z Why y is documentation important p ? z Manage

the Project z Obtain Consensus ITM Lecture 6 Advanced Diploma (Thames College)

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Manage a age the t e Project P oject z Documentation

is a tool used to manage g the development process. This is done in a ew ways. few z It

is used to review tasks which have been completed or which are going to be done. z It is used to monitor progress and take corrective action. action z It is used to make decisions on future tasks. z It is i the th tools t l usedd to t manage m n the th development process, to control its activities and plan future steps steps. ITM Lecture 6 Advanced Diploma (Thames College)

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Obtain Consensus Obta Co se sus z In

any complex task involving many parties parties, there is always a possibility of misunderstanding. z The Th agreementt should h ld be b ddocumented t d andd a copy py sent to all parties p involved for feedback and agreement. While this does not guarantee that there will not be any miscommunication, it does minimize it. ITM Lecture 6 Advanced Diploma (Thames College)

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Questions & Discussion

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