chapter 23

• wide variety of computer hardware and software technology; used to manage and control information.

  Information technology
• MAJOR COMPONENTS OF AN INFORMATION SYSTEM

  1. Hardware
  2. Software
• Software is of two major types:

  1. System software
  2. Application software
• Types of application software

  1. Data
  2. People
  3. Procedures
  4. Networks
• Five fundamental functions of an information system:

  1. Capture input
  2. Process
  3. Convey outputs
  4. Collect feedback
  5. Controls
• Input can come from many different types of devices including

  • data entered via keyboard, a mouse, barcodes, RFID tags, scanning devices, or voice-enabled applications such as Siri and Alexa. 
• a system that allows immediate update or access to data, or instantaneous analysis of data.

  Real-time or online processing
• interconnects computer within a limited area, typically a building or a small cluster of buildings.

  Local area network (LAN)
• interconnects computer within a large geographical area.


  Wide area network (WAN)
• INTERNAL CONTROL IN AN IT ENVIRONMENT 

  • General control activities
  • Application control activities
  • User control activities 
• The five categories of general controls are:

  • organization and operation controls
  • systems development and documentation controls
  • hardware and systems software controls
  • access controls
  • data and procedural controls. 
• Two common controls over system change include the following: 

  1. Design Methodology
  2. Change control process
• Hardware and systems software controls

  1. Parity check
  2. Echo check
  3. Diagnostic routines
  4. Boundary protection
  5. Periodic maintenance
• Data and procedural controls: to prevent unnecessary stoppages or errors in processing, the following specific controls should be implemented:

  1. Operations run manual
  2. Backup and recovery
  3. Contingency processing
  4. Processing controls
  5. File protection ring
  6. Internal and external labels
• Input controls: to ensure the integrity of the human readable data into a computer readable format, there are many common controls that can be used.

  1. Preprinted form
  2. Checker digit
  3. Control batch
  4. Hash totals
  5. Record count
  6. Reasonableness and limit tests
  7. Menu driven input
  8. Field checks
  9. Validity checks
  10. Missing data check
  11. Field size check
  12. Logic check