1. 1.2 System Design Basics

2. Components of a computer system
Hardware
Software
Peripheral
Network
Human resource

3. Scenario
The library needs a way of keeping track which students have come into the library in the morning, during lunch, and after school
What components are needed in the solution’s system?
Computer
Software / application / website
Keyboard / Mouse / Touchpad
Network (optional?)
Database (optional?)
Librarian

4. What are stakeholders? Stakeholder -
Scenario: The library check-in system
Stakeholders – people with a vested interest; people who are impacted
E.g. librarians, administration, students; teachers

5. Stakeholders’ Requirements
What are different ways to obtain requirements from stakeholders?
Ask them
Surveys
Questionnaires
Interviews
Watch them / observations

6. What other ways are there to gather information to solve the problem?
Background research
Pre-existing documents
Look at other solutions

7. System Design Cycle Analysis Design Implementation Operation
Collect and examine data
Analyze current system and data flow
Design
Plan your system, its data flow, data structures, algorithms, and modules
Implementation
Schedule implementation goals and milestones
Testing
Operation
Installing the system
How to use it? (documentation!)
Maintenance
Finding bugs and patching them
How and why is it cyclical?
What steps are the end-user involved in? Why?
Cyclical because the process would be repeated for the next version of the system
End-user should be involved in all steps
Earlier feedback is better and saves money

8. Prototyping A very simple version of the system
Preliminary solution ~ a prototype!
Prototype used to get feedback before you spend too much time building the actual system
Example:
storyboarding a movie

9. Implementation Testing
User acceptance testing
Testing the system if it handles all of the end-user requirements
Example: Go through checklist of requirements and the system has it all
Example: Giving it automated test data and matching it to expected results
Debugging
Fixing your code when you test different types of data (normal, abnormal, extreme)
Beta testing
End-user testing  obtain feedback and crash reports

10. Different installation processes
Direct changeover
Phased conversion
Pilot running
Parallel running
What are the advantages/disadvantages of each?
Direct changeover
+ quick, cheap, saves money
- risky, no backup if it fails, no transition time
Phased conversion
+ less risky, more time to transition and test out parts
- more expensive
Pilot running
+ test out system with a small group first; receive feedback before larger deployment
- pilot group must try to use new system
Parallel running
+ old system still runs as a backup; compare results of new system with old system
- expensive b/c running both systems at the same time

11. What are the different ways to maintain/update the system?
Automatic
Manual
Hybrid of the two (automatic check with manual confirmation)

12. User Documentation What is it? Why is it important?
What are different ways to provide user documentation? (e.g. help files)
Advantages/Disadvantages of each?
Any documentation for the user to learn how to use the system
User manual / printed manuals
Help files
On-line support
Tutorials

13. User Training What are different ways to train your user?
Advantages/Disadvantages of each?
In-person / Formal classes
+ live help and feedback
- expensive
Remote training
+ training can be received anywhere from a remote instructor
- harder to interact with teacher
On-line learning
+ training can be accessed at any time at user’s pace
- not able to receive feedback from a human
Self-instruction
+ training can be done at any time at user’s pace

14. What is usability? Usability –
Usability ~ ease of use and learnability of a human-made thing

15. Examples of things that improved usability
Mouse
Touchscreens
Graphical User Interface
System messages with feedback

16. What are examples of bad usability?
Messy / busy / cluttered user interfaces
Hard to hit targets
Unintuitive menus and design

17. Usability Guidelines