CIS 115
Software Engineering
What is Software Engineering?
Study of how to best create software efficiently while maximizing the "quality" of the resulting software
1945 - 65: Early Software
- Many software pioneers were women!
- Early computers were very specialized; software was rewritten
- Led to high-order languages like FORTRAN, COBOL, ALGOL
- Conferences held in 1968 and 1969 started the field
1965 - 85: Software Crisis
- Many projects ran over budget and schedule
- Bad software could cause damage or even death!
- The field needed to be standardized
1985 - 89: No Silver Bullet
- Unfortunately, no single solution to make software better
- 1995 study: 1/2 of software projects operational but not successful
- Average software project overshoots schedule by half
- 3/4 of large software projects either not used or don't meet all requirements
1990 - 2000: Rise of the Internet
- Software made more use of the network
- Graphics became more important
- Software was becoming more and more consumer focused
- Viruses, search engines, email, etc.
2000 - Present: Lightweight Methodologies
- Agile development: focus on velocity
- Use of models and reused code to ease development
- Software "families" avoid the need to recreate software from scratch
Software Development Life Cycle
- Requirements
- Specification
- Architecture
- Construction & Design
- Testing & Debugging
- Deployment & Maintenance
Requirements Elicitation
- Contact stakeholders
- Gather information
- List requirements
- Determine target & goals
- Use Cases
- Verify correctness
Software Specification
- Describes how the system should function
- Lists inputs and outputs
- Should clearly match the requirements
Software Architecture
- High-level overview of how the software should be built
- Accounts for multiple stakeholders, separation of concerns, recurring styles or models, etc.
- Gives developers a framework to work with
Software Design & Construction
- Developers refine the architecture diagram by adding features and solidifying individual design components
- Usually several layers of diagrams are made for larger software projects
Software Testing & Debugging
- Verifying the software works correctly
- Errors can be introduced at any step of the process
- Unfixed errors can cause massive problems down the road
- The longer an error is unfixed, the more it takes to fix it
Deployment & Maintenance
- Once software is created, it must be given to clients
- Larger software packages require more deployment effort
- Once software is deployed, bugs may still be found and must be patched
- Updates may be issued to add more features
Development Models
- Code & Fix
- Waterfall
- Iterative / Incremental
- Spiral
- Agile
Source: Agile Manifesto
Globalization
- Software is GLOBAL!
- Companies can "follow the sun"
- Development can happen 24 hours a day
- Communication and collaboration is key to success
Assignments
- Read and be prepared to discuss:
- Tubes Chapter 5: Cities of Light
- Topic Research Project! - Due 3/11 10:00 PM
- Blog 4: The Internet's Influence - Due 3/21 10:00 PM
Blog 4: The Internet's Influence
The internet has been a major force in our lives for several decades now. Write about how the internet has influenced you as a person. Try and think about ways that you would be a different person if you didn’t have the internet. Things you can think about:The internet is a very influential part of our modern culture. Because of this, most of us have been impacted by the internet in some way throughout our lives. For this blog article, write about how the internet has impacted you as an individual, but also how you believe the internet has impacted us as a society in general. (Food for thought: - read about the Filter Bubble or Cyberculture for ideas: https://en.wikipedia.org/wiki/Filter_bubble and https://en.wikipedia.org/wiki/Cyberculture). As you are writing, here are some things you can think about:
- How do you typically communicate with friends and family today? Has it changed over the years?
- Do you ever find yourself without access to the internet? How does that make you feel?
- Have you met friends online? Is that different than meeting them in person?
- Where do you typically get your information and news? Do you see the same information that other people see? How do you verify the authenticity and accuracy of that information?
- What would happen if the internet were to disappear tomorrow?
- Do you feel secure on the internet? Do the recent revelations about government tracking and large security breaches affect how you use the internet?
- How has Tubes helped you understand how the internet works so far?
- Are the other interesting articles or opinions about the internet that you found?
Topic Research Project