Systems Analysis & Design Introduction

Systems Analysis & Design

Introduction

Karolina Muszyńska

Based on http://www.csun.edu/~dn58412/IS431/IS431_SP13.html

Information system applications - WHAT Information systems and their

stakeholders – WHO Definition of a system Role of systems analysts Knowledge and skill set for system

analysts IS Building Blocks Business modeling – why, what, how?

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System Development Environment: Participants and

Context

Information System (IS): People, data, processes, and information technology that interact to collect, process, store, and provide as output the information needed to support and improve operational, tactical, and strategic activities of an organization (business).

Information Technology (IT): A combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks)

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Information Systems vs. Information Technology

Data – raw facts about people, places, events, and things that are of importance in an organization.

Information – data that has been processed or reorganized into a more meaningful form for someone.

Knowledge – data and information that is further refined based on the facts, truths, beliefs, judgments, experiences, and expertise of the recipient.

Wisdom – when to apply a certain knowledge

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From Facts to Knowledge

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Decision-Making in an Organization

Executive Level◦ Long-term decisions (Strategies)◦ Unstructured decisions (Competitions)

Managerial Level◦ Decisions covering weeks and months (Tactics)◦ Semi-structured decisions (Effectiveness)

Operational Level◦ Day-to-day decisions (Operations)◦ Structured decisions (Efficiency)

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Decision-Making Levels of an Organization

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STRATEGIC

OPERATIONAL

EXECUTIVE INFORMATION SYSTEMS

MANAGEMENT INFORMATION SYSTEMS

TRANSACTION PROCESSING SYSTEMS

ACCOUNT I NG

F I NANCE

HUMAN  RES

PRODUCTION

SALES

OTHERS

TACTICAL

VALUE CHAIN

  Information Systems in Organization

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Information System in Context

Transaction Processing Systems Management Information Systems Executive Information Systems Decision Support Systems Expert Systems Functional Area Information Systems

(Accounting, HR, Sales, Production …) Office Automation Systems (Personal

Productivity Software) Collaboration Systems (Groupware) Enterprise Systems

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Types of Information Systems

Front-office information systems support business functions that extend out to the organization’s customers (or constituents).◦ Marketing◦ Sales◦ Customer management

Back-office information systems support internal business operations of an organization, as well as reach out to suppliers (of materials, equipment, supplies, and services). ◦ Human resources◦ Financial management◦ Manufacturing◦ Inventory control

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Front- and Back-Office Information Systems

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A Federation of Information Systems

Stakeholder: any person who has an interest in an existing or proposed information system. Stakeholders can be technical or nontechnical workers. They may also include both internal and external workers.

Information workers are those workers whose jobs involve the creation, collection, processing, distribution, and use of information.

Knowledge workers are a subset of information workers whose responsibilities are based on a specialized body of knowledge.

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Stakeholders of a System

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Perspectives on an Information System

System owners – an information system’s sponsors and executives advocate, usually responsible for funding the project of developing, operating, and maintaining the information system. They define the SCOPE of a system: what business problem is to be solved◦ They view the system in terms of cost/benefit to

solve business problem

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System Owners

System users – use or are affected by an information system on a regular basis – capturing, validating, entering, responding to, storing, and exchanging data and information. They define the REQUIREMENTS of the system.◦ Internal users

Clerical and service workers Technical and professional staff Supervisors, middle managers, and executive managers Remote and mobile users (internal but disconnected)

◦ External users

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System Users

System designers translate system users’ business requirements and constraints into technical solution: computer databases, inputs, outputs, networks, and software meeting the system users’ requirements. Their activities relate to the DESIGN of a system

System builders construct information systems based on the design specifications from the system designers. Their activities relate to building the COMPONENTS of the system.

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System Designers and System Builders

Systems analysts study the problems and needs of an organization to determine how people, data, processes, and information technology can best accomplish improvements for the business. They are FACILITATORS of the system development project.• A programmer/analyst (or analyst/programmer)

includes the responsibilities of both the computer programmer and the systems analyst.

• A business analyst focuses on only the nontechnical aspects of systems analysis and design.

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Systems Analysts

What “problems” to solve: (Project Definition)◦ True problem situations, either real or anticipated, that

require corrective action◦ Opportunities to improve a situation despite the

absence of complaints ◦ Directives to change a situation regardless of whether

anyone has complained about the current situation Why: (Project Justification)

◦ Effective: Do right thing◦ Efficient: Do thing right◦ Competitive: Do thing differently

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The Systems Analyst as a Problem-Solver

In traditional businesses◦ Working in traditional information services organizations

(permanent project teams)◦ Working in contemporary information services

organizations (dynamic project teams) In outsourcing businesses

◦ Contracted to traditional businesses In consulting businesses

◦ Contracted to traditional businesses In application software businesses

◦ Building software products for traditional businesses

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Systems Analysts At Work

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Systems Analyst as a Facilitator

Working knowledge of information technology Computer programming experience and expertise General business knowledge General problem-solving skills Good interpersonal communication skills Good interpersonal relations skills Flexibility and adaptability Character and ethics Systems Analysis and Design Skills

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Skills Needed by the Systems Analyst

Information systems architecture - a unifying framework into which various stakeholders with different perspectives can organize and view the fundamental building blocks of information systems.

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Information Systems Architecture

KNOWLEDGE (Data) — the raw material used to create useful information.

PROCESSES — the activities (including management) that carry out the mission of the business.

COMMUNICATION (Interfaces) — how the system interfaces with its users and other information systems.

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Focuses for Information Systems

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System owners’ view◦ Interested not in raw data but in information that adds

new business knowledge and information that help managers make intelligent decisions.

◦ Data entities and business rules.

System users’ view◦ Something recorded on forms, stored in file cabinets,

recorded in books and binders, organized into spreadsheets, or stored in computer files and databases.

◦ Focus on the business issues as they pertain to the data.◦ Data requirement – a representation of users’ data in

terms of entities, attributes, relationships, and rules independent of data technology.

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KNOWLEDGE Focus

System designers’ view◦ Data structures, database schemas, fields,

indexes, and constraints of particular database management system (DBMS).

System builders’ view◦ SQL◦ DBMS or other data technologies

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KNOWLEDGE Focus …

System owners’ view ◦ Concerned with high-level process called business

functions◦ Business function – a group of related processes that

support the business. Functions can be decomposed into other subfunctions and eventually into processes that do specific tasks. (e.g. Sales Function)

◦ A cross-functional information system – a system that supports relevant business processes from several business functions without regard to traditional organizational boundaries such as divisions, departments, centers, and offices. (e.g. Production Function)

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PROCESS Focus

System users’ view ◦ Concerned with work that must be performed to provide

the appropriate responses to business events. ◦ Business processes – activities that respond to

business events.◦ Process requirements – a user’s expectation of the

processing requirements for a business process and its information systems.

◦ Policy – a set of rules that govern a business process.◦ Procedure – a step-by-step set of instructions and logic

for accomplishing a business process.◦ Work flow – the flow of transactions through business

processes to ensure appropriate checks and approvals are implemented.

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PROCESS Focus …

System designers’ view◦ Concerned with - which processes to automate

and how to automate them◦ Constrained by limitations of application

development technologies being used◦ Software specifications – the technical design

of business processes to be automated or supported by computer programs (off-shelf, in-house) to be written by system builders.

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PROCESS Focus …

System builders’ view◦ Concerned with programming logic that implements

automated processes◦ Application program – a language-based, machine-

readable representation of what a software process is supposed to do, or how a software process is supposed to accomplish its task.

◦ Prototyping – a technique for quickly building a functioning, but incomplete model of the information system using rapid application development tools.

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PROCESS Focus …

System owners’ view◦ Concerned with communications scope of an

information system. Who (which business units, employees, customers,

and partners) must interact with the system? Where are these business units, employees,

customers, and partners located? What other information systems will the system

have to interface with?

System users’ view◦ Concerned with the information system’s inputs

and outputs (Interface Requirements).

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COMMUNICATION Focus

System designers’ view◦ Concerned with the technical design of both the user and

the system-to-system communication interfaces.◦ Interface specifications – technical designs that

document how system users are to interact with a system and how a system interacts with other systems.

◦ User dialogue – a specification of how the user moves from window to window or page to page, interacting with the application programs to perform useful work.

System builders’ view◦ Concerned with the construction, installation, testing and

implementation of user and system-to-system interface solutions.

◦ Middleware – utility software that allows application software and systems software that utilize differing technologies to interoperate.

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COMMUNICATION Focus …

System initiation – the initial planning for a project to define initial business scope, goals, schedule, and budget.

System analysis – the study of a business problem domain to recommend improvements and specify the business requirements and priorities for the solution.

System design – the specification or construction of a technical, computer-based solution for the business requirements identified in a system analysis.

System implementation – the construction, installation, testing, and delivery of a system into production.

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System Development Process Overview

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System Development as Problem Solving

Business Modeling: Why, What , How ?

An IS professional can add value in helping an organization to define and improve its business processes and design appropriate IS.

What are business processes and how can they be designed to support an organization’s objectives?

How do we design information systems that collect, maintain, and process the data needed to generate the outputs required by management to effectively manage business processes in the information age?

REAL Business Process Modeling

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Business Processes

Acquisition/Payment Business Process

Human ResourcesFinancial ResourcesSuppliesInventoriesProperty, Plant and EquipmentNew Ideas (R & D)Miscellaneous services

Conversion Business Process

Operations

(Varies widely depending upon the industry)

Sales/CollectionBusiness Process

Marketing and SalesServicePromotionOutbound logisticsCollection and CreditE-CommerceA

CT

I VI T

IES

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Acquisition/Payment Process Regardless of the type of good or service being

acquired, the following are typical operating events in the acquisition/payment business process:◦ Request goods or services.◦ Order goods or services.◦ Receive and inspect goods or services.◦ Store and/or maintain goods.◦ Pay for goods or services.◦ Return goods.

Specifics may vary

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Sales/Collection Process Although there is some diversity across the types

of goods and services sold, the sales/collection process typically includes the following events:◦ Receive an order for goods or services.◦ Select and inspect goods or services to be delivered.◦ Prepare goods or services for delivery.◦ Deliver goods or services.◦ Receive payment for goods or services.◦ Accept customer returns of goods.

Specifics may vary

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Conversion Process General activities in the conversion process include:

◦ Assembling.◦ Growing.◦ Excavating.◦ Harvesting.◦ Basic manufacturing (e.g., metals, woods, and chemicals).◦ Finished manufacturing (e.g., tools, instruments,

components).◦ Cleaning.◦ Transporting.◦ Distributing.◦ Providing (e.g., power, water, protection, communication).◦ Training.◦ Discovering (e.g., research and development).

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Business Process Events A business process is “a series of activities intended to

accomplish the strategic objectives of an organization.” Operating Events are the operating activities performed

within a business process to provide goods and services to customers.

Information Events include three activities: recording data about operating events, maintaining reference data that are important to the organization, and reporting useful information to management and other decision makers.

Decision/Management Events are activities where management and other people make decisions about planning, controlling, and evaluating business processes.

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Business Process: Delivering Goods and Collecting Payment

Event 1: Marketing

Event 2: Take Customer

Order

Event 3: Ship the

Goods

Event 4: Collect Payment

Business Process and Business Events

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Business Process Activities (Events)

Decision/ management

events

Operatingevents

Informationevents

Define &Trigger

Trigger Trigger

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TriggerReport

(in many formats)

Record (event data)Maintain

(agent, resource, location data)

Trigger

Processes that Trigger Information System Responses

Business events

Informationprocesses

Informationprocesses

Information Needs of Decision Makers

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Analyzing the market, competitors, and customers.

Deciding what pizzas to place on Golden’s menu.

Determine if the cooked pizza is correct for presenting order form.

Receive customer pizza order.

Receive customer payment.

Make pizza. Deliver pizza to

customer.

Decision/Management Operating Events Information Events

Process Analysis: Golden Pizza

Generate a customer analysis report.

Generate a report of sales by pizza type.

Generate a gross margin analysis.

Generate a report of lost sales (due to the 20 minutes guarantee.)

Trigger

Trigger

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Developing a REAL Business Process Model

REAL Business Process Modeling is a formal method of identifying and representing the essential characteristics that collectively describe business processes and events.

REAL = Resources, Events, Agents, and Locations. Preparing a REAL Business Process Model requires

the identification of strategically significant business activities and essential characteristics about these business activities.

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Developing a REAL Business Process Model …

Step 1: Understand the organization’s Environment and Objectives

Step 2: Review the business process and identify the strategically significant operating events

Step 3: Analyze each event list in #2 to identify Resources, Events, Agents, and Locations

Step 4: Identify the relevant behaviors, characteristics, and attributes of REAL

Step 5: Identify and document direct relationships within REAL

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Step 1: Understand The Organization’s Environment and

Objectives REAL modeling is an aid in analyzing an organization

and its activities. Collect data and insights about the organization’s

objectives, industry, value chain, strategies, product lines, and customers.

Pay attention to the organization’s people, structure, technologies, and measurements.

A better understanding of these factors will enhance the evaluation of effective and efficient business processes valuable, competitive, meeting the organization’s objectives.

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Understanding the Business Environment

IndustryThe Company

Competitors

Technologies

Customers

EconomicForcesPeople

CapitalTechnology

Value Chain Products

Structure

Objectives

Strategies

Measurements

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Step 2: Review the Business Process and Identify the Strategically Significant Operating Events

Begin by dividing the organization into its business processes. “What happened? How and Why? ”

REAL graphical model—include the strategically significant operating events that comprise a business process. (The ones that the organization wants to plan, evaluate and execute/or control)

Begin REAL graphical model by representing events with a descriptor.

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Step 2 example: MrKool’s Retail Model

Events

Sellmerchandise

Receivecustomerpayment

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Step 3: Analyze Each Event Listed in Step 2

to Identify R E A L Describe essential characteristics of the

Events—the characteristics which:◦ if omitted, would render an inaccurate or incomplete

description of the event.◦ form the basis for generating outputs for information

customers to plan, execute, control and evaluate organization activities.

What kinds of Resources were involved? What roles are performed and who/what

Agents perform the roles? Where did the event occur? (Location)

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Step 3 example: MrKool’s REAL Model

Sell Merchandise

ReceiveCustomer Payment

Merchandise

Cash

Register

Salesperson

Customer

RESOURCES/ LOCATION

EVENTS AGENTS

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Step 4: Identify the Relevant Behaviors, Characteristics, and

Attributes of REAL At what time or sequence in the process should

the event occur? What are the exceptions to the “normal”

ordering of events in the process? What is the proper authorization or approval to

execute this event? What is a reasonable amount of resources

associated with this event? What are the acceptable locations for executing

this event?

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Step 4 example: MrKool’s REAL Model

What is an acceptable time period between events in a business process?

How might the order of events vary by customer? Does the location from which goods are shipped

matter? How many salespeople are assigned to each

customer? Should a sales order clerk have custody of cash?

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Sequence of Events

The sequence of events may also be a function of the physical characteristics of the event (in production)

Sometimes the sequence of events is dictated by business policy

Receive payment

Ship merchandiseReceive payment

Ship merchandiseOR

Provide Credit Cash in Advance

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Example: MrKool’s Business Rules

Each sale takes place at a specific register (location).

Each sale involves only one customer (external agent).

Only one salesperson (internal agent) is responsible for each sale.

Each sale involves one or more items of merchandise (resource).

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Additional rules:◦ The salesperson and customer do not have a direct

relationship, The customer and salesperson are related only through the sale.

◦Sales can only involve merchandise, not fixed assets.

◦Sales cannot involve more merchandise (quantity) than McKool has on hand.

◦Sales cannot involve merchandise McKool does not offer.

◦The store keeps records on who sold which merchandize to whom at a specific cash register

Example: MrKool’s Business Rules …

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Step 5:Identify and Document Direct Relationships within REAL

Draw a line from each event to each resource, internal agent, external agent, and location associated with that event. On the line, add a meaningful term or phrase that describes the relationship between the objects.

Graphically display events that are related to other events to show the required sequence of events in a business process. Draw lines from event to event in the correct sequence

Document direct relationships between pairs of agents, locations, and resources that exist independently of an operating event. Connect the pairs with a line.

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Step 5 example: MrKool REAL Model

Sell Merchandise

ReceiveCustomer Payment

Merchandise

Cash

Register

Salesperson

Customer

involves

takes

place at

takes place at

increasesinternal agent

internal

agent

external

agent

external agent

results in

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Linking Processes Business processes are linked together in two

ways: ◦ sharing common resources or ◦ an event in one process triggering an event in another

process. Collectively business processes result in the

acquisition of goods and services the conversion of acquired goods and services into goods and services for customers the delivery of the goods and services to customers the collection of payment from customers.

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Linked Processes

Acquisition

Inventory

Sales

Collection

(Share a common Resource)

(One triggers another)

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Summary: A Model of Business Events

• What happened?• When did it happen?• Who was involved?• What resources were involved?• Where did it occur?

Event

Internal Agents

Location ExternalAgents

Resources

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From REAL Model ...

Inventory

Cash

Sales Salesperson

Customer

CashCollection

Cashier

Resources Events Agents

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…to ERD

Inventory

Cash

SalesSalesperson

Customer

CashCollection

Cashier

Include

Include

Pay for

Sell

Sell to

Receivefrom

Receive by

M M

M

M

M

M

M

M

M1

1

1

1

1

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