ZeePedia buy college essays online


Information Systems

<<< Previous Open-Loop System, Closed Loop System, Open Systems, Closed Systems, Level of Planning Next >>>
 
img
VU
Information System (CS507)
LESSON 7
Types of Systems
7.1 What are Systems?
A system is a group of elements that are integrated with the common purpose of achieving an objective.
Example
Purchase & Sales System
7.2 Components of a system
Following are the important components of the system.
Input elements
Raw Data input to the computer system
Process
Computation, analysis, application of any model
Output elements
Results of computation or analysis
Control mechanism
Comparison of actual with expected
Feedback system
Corrective action
Objectives
Expected/Ideal output
7.3 Types of Systems
7.3.1 Open-Loop System
The determinant factor is in an open loop system is that the information from the system not used for
control purpose. This is done by using the output to generate feed back for control purposes.
The output is not coupled to the input for measurement.
Hence the components of open loop system do not include control and feedback mechanism due to
non-existence of internally defined objectives. That is,
o  Input
o  Process
o  Output
Example
An information system that automatically generates report on regular basis and are not used to monitor
input or activities.
7.3.2 Closed Loop System
Is a system where part of the output is fed back to the system to initiate control to change
Either the activities of the system or input of the system
Has the ability to control the output due to existence of
20
img
VU
Information System (CS507)
Control Mechanism
Feedback System
Objectives
Example
Budgetary control system in a company by which
o  The results are communicated through feedback system
o  Results are compared with the objectives/budget through controls mechanism
7.3.3 Open Systems
A system that is connected to its environment by means of resource flows is called an open system.
The environment exerts influence on the system and the system also influences the environment.
Example
Business is a system where management decisions are influenced by or have an influence on suppliers,
customers, society as a whole.
Computerized system of a manufacturing entity, that takes influence from the society.
7.3.4 Closed Systems
A system that is not connected with its environment
Neither environment exerts any influence on the system nor does system influence the environment.
Examples
An information system designed to control data in a research laboratory is a closed system.
An information system designed to record highly sensitive information is a closed system so as
To accept no input for amendment
To give no output for disclosure
Objective of Having Systems
To subject a predefined amount of input (tangible, intangible) to predefined set of instructions in order
to achieve an expected quality and amount of output.
Effective and efficient utilization of resources
7.4 Level of Planning
There are three levels
Strategic
Tactical / Functional
Operational
21
img
VU
Information System (CS507)
Strategic Planning
Is the formulation, evaluation and selection of strategies for the purpose of preparing a long-term plan of
action to attain objectives.
Tactical/Functional Planning
Is the process by which managers assure the resources are obtained and used effectively and efficiently in
the accomplishment of the organization's objectives?
Operational Planning
It is the process of assuring that the specific tasks are being carried out efficiently and effectively.
Functional Strategic Planning
Commitment by Firm's executives requires strategic planning for the following functional areas.
o  Manufacturing resources
o  Financial resources
o  Human resources
o  Marketing Resources
o  Information Resources
7.5 Strategic Planning for Information Resources (SPIR)
When a firm embraces SPIR the strategic plans for information services and the firm are developed
concurrently. Business strategy and IT related strategy should go hand in hand. The IT related strategy
should be driven by business strategy and the former should support the achievement what's being
mentioned in the latter. Any inconsistencies or deviations between the two should be removed and avoided.
The investment in IT is costly and inflexible. Such investment is also monitored and controlled by the IT
strategy. Hence any investment not supporting the business strategy would be futile.
Example
Business strategy
Modify inventory system to fulfill orders quickly through relocating system to warehouse and efficient
shelf picking.
IS strategy
To identify information resources needed for the successful implementation of business strategy.
Information Value Chain
Raw information is transformed at various points and value is added before passing onwards. Every step of
processing should make the information stored more valuable.
Example
When customer order received, data punched into computerized system, which updates order list, customer
records and store room records. When order has been served, customer orders are filed into records.
22
Table of Contents:
  1. Need for information, Sources of Information: Primary, Secondary, Tertiary Sources
  2. Data vs. Information, Information Quality Checklist
  3. Size of the Organization and Information Requirements
  4. Hierarchical organization, Organizational Structure, Culture of the Organization
  5. Elements of Environment: Legal, Economic, Social, Technological, Corporate social responsibility, Ethics
  6. Manual Vs Computerised Information Systems, Emerging Digital Firms
  7. Open-Loop System, Closed Loop System, Open Systems, Closed Systems, Level of Planning
  8. Components of a system, Types of Systems, Attributes of an IS/CBIS
  9. Infrastructure: Transaction Processing System, Management Information System
  10. Support Systems: Office Automation Systems, Decision Support Systems, Types of DSS
  11. Data Mart: Online Analytical Processing (OLAP), Types of Models Used in DSS
  12. Organizational Information Systems, Marketing Information Systems, Key CRM Tasks
  13. Manufacturing Information System, Inventory Sub System, Production Sub System, Quality Sub system
  14. Accounting & Financial Information Systems, Human Resource Information Systems
  15. Decision Making: Types of Problems, Type of Decisions
  16. Phases of decision-making: Intelligence Phase, Design Phase, Choice Phase, Implementation Phase
  17. Planning for System Development: Models Used for and Types of System Development Life-Cycle
  18. Project lifecycle vs. SDLC, Costs of Proposed System, Classic lifecycle Model
  19. Entity Relationship Diagram (ERD), Design of the information flow, data base, User Interface
  20. Incremental Model: Evaluation, Incremental vs. Iterative
  21. Spiral Model: Determine Objectives, Alternatives and Constraints, Prototyping
  22. System Analysis: Systems Analyst, System Design, Designing user interface
  23. System Analysis & Design Methods, Structured Analysis and Design, Flow Chart
  24. Symbols used for flow charts: Good Practices, Data Flow Diagram
  25. Rules for DFDs: Entity Relationship Diagram
  26. Symbols: Object-Orientation, Object Oriented Analysis
  27. Object Oriented Analysis and Design: Object, Classes, Inheritance, Encapsulation, Polymorphism
  28. Critical Success Factors (CSF): CSF vs. Key Performance Indicator, Centralized vs. Distributed Processing
  29. Security of Information System: Security Issues, Objective, Scope, Policy, Program
  30. Threat Identification: Types of Threats, Control Analysis, Impact analysis, Occurrence of threat
  31. Control Adjustment: cost effective Security, Roles & Responsibility, Report Preparation
  32. Physical vs. Logical access, Viruses, Sources of Transmissions, Technical controls
  33. Antivirus software: Scanners, Active monitors, Behavior blockers, Logical intrusion, Best Password practices, Firewall
  34. Types of Controls: Access Controls, Cryptography, Biometrics
  35. Audit trails and logs: Audit trails and types of errors, IS audit, Parameters of IS audit
  36. Risk Management: Phases, focal Point, System Characterization, Vulnerability Assessment
  37. Control Analysis: Likelihood Determination, Impact Analysis, Risk Determination, Results Documentation
  38. Risk Management: Business Continuity Planning, Components, Phases of BCP, Business Impact Analysis (BIA)
  39. Web Security: Passive attacks, Active Attacks, Methods to avoid internet attacks
  40. Internet Security Controls, Firewall Security SystemsIntrusion Detection Systems, Components of IDS, Digital Certificates
  41. Commerce vs. E-Business, Business to Consumer (B2C), Electronic Data Interchange (EDI), E-Government
  42. Supply Chain Management: Integrating systems, Methods, Using SCM Software
  43. Using ERP Software, Evolution of ERP, Business Objectives and IT
  44. ERP & E-commerce, ERP & CRM, ERP Ownership and sponsor ship
  45. Ethics in IS: Threats to Privacy, Electronic Surveillance, Data Profiling, TRIPS, Workplace Monitoring