1. “Software's Chronic Crisis” by W. Wayt Gibbs
Presented by Daniel Thomasset
EECS Fall 2005

2. Organization Software's chronic crisis
Factors contributing to the crisis
challenges of large software
case studies
impacts of software failures
The need for software engineering
software engineering defined
Software engineering techniques
CMM
Standardization
Concluding remarks

3. Software's Chronic Crisis
The software crisis is chronic
chronic
- of long duration, continuing
- marked by frequent reoccurance
crisis
- a crucial state of affairs in which a decisive change is impending; especially one with the possibility of an undesirable outcome
Definitions: Merriam-Webster Dictionary, online

4. Challenges of Large Software
Distributed and realtime systems
distributed software is complex and has more paths of failure
Human comprehension
No single person can completely comprehend a large project
Growth in hardware complexity
hardware complexity doubles every 18 months
Lack of standardization
interfaces and methods for software construction can differ
Lack of measurement
time and cost are hard to estimate without empirical knowledge of the organization's capabilities

5. Case Study: Denver Airport
A complex distributed software system
baggage delivered by 4000 automated “telecars”
100 computers controlled movement using electric eyes, bar-code sensors, and radio receivers
cost $193M for initial implementation
Over budget, operating failure
failure delayed airport opening one year (cost >$1M per day)
canceled in August 2005
Reasons for failure
high maintenance costs: $1M per month
couldn't handle real-world errors
Sources: Johnson, 2005 and Gibbs, 1994

6. Impacts of Software Failures
Business impacts from IBM Consulting Group survey
55% of projects cost more than expected
68% took longer than estimated to complete
88% of projects had to be substantially redesigned
Failed projects are not used
75% of large projects are operating failures or not used at all
Public safety can be affected
software controls trains, aviation, life support systems, and nuclear power plants

7. Case Study: Federal Aviation Administration (FAA)
Advanced Automation System (AAS)
replacement air-traffic control system
contracted to IBM in 1983 with a budget of $2.6 billion
>1M lines of code, 100s of computers
Over budget, late, and unfinished
in 1996, General Accounting Office (GAO) reports 57% of the budget was wasted
2/3 of project is canceled, the rest is late
Reasons for failure
FAA assumed that IBM would use engineering techniques
GAO reports that “human factors” were the main reason for failure
Sources: House, 2001 and Gibbs, 1994

8. Need for Software Engineering
Software development is preindustrial
“It's like musket making was before Eli Whitney”
artisans using little standardization
each piece is unique
Consistent software quality requires a process
“If we are ever going to lick this software crisis, we're going to have to stop this hand-to-mouth every-programmer-builds-everything-from-the-ground-up, preindustrial approach”
Quotes: Brad Cox in Gibbs, 1994

9. Software Engineering
First defined in1968 by the NATO Science Committee
50 software experts met to solve the software crisis
defined software engineering as “the application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software”

10. The Engineering Process
Important aspects of an engineering discipline
systematic
- establishes standard practices
- allows repeatable results
quantifiable
- allows comparison of systems
- allows estimation of time, cost,
The process of improvement
a systematic and quantifiable system allows for continuous process improvement
the cycle
1. establish a system, do a project, measure the results
2. evaluate and refine the system
3. goto step 1

11. Capability Maturity Model
The Capability Maturity Model (CMM)
developed by the Software Engineering Institute (SEI)
a quantifiable engineering process applied to software development that “provides a vision of software engineering and management excellence”
defines levels of maturity from 1 to 5.
updated version called Capability Maturity Model Integration (SEI, 2005)
Results of Raytheon's transition from Level 1 to 3
most projects completed ahead of schedule and under budget
productivity doubled
savings of $7.80 for every dollar invested in CMM
Quote: David Zubrow in Gibbs, 1994

12. CMM Levels

13. Other Techniques Formal Methods Growing Software Cleanroom
mathematically prove that the algorithm is correct
Growing Software
start simple and grow until complete
Cleanroom
combines formal methods, statistical quality control, and evolutionary approach
analogous to a hardware clean room - don't let in the bugs

14. Standardization Standard software pieces Standard processes Results
interfaces become simpler
allows standard tests
Standard processes
forces all software developers to use best-practices
may require government involvement and licensing
Results
increases reliability
reduces repeated mistakes
facilitates budget estimation

15. Summary Software's chronic crisis Factors contributing to the crisis
challenges of large software
case studies
impacts of software failures
The need for software engineering
software engineering defined
Software engineering techniques
CMM
standardization

16. Conclusions Software development is hard
complexity will always cause challenges
Software engineering improves the process
continuous improvement possible with method and measurement
Industry is making progress
in 1994, two CMM level 5 organizations
today, eighty-five CMM level 5 organizations (SEI, 2005)
Slow, directed growth
there's no “silver bullet”
research is required to make improvements in the process

17. Bibliography
Gibbs, W. Wayt, “Software's Chronic Crisis”, Scientific American, September 1994.
House of Representatives, Aviation Subcommittee, “FAA's efforts to modernize the Air Traffic Control system”, March 14, 2001.
Johnson, Kirk, “Denver Airport Saw the Future: It Didn't Work”, New York Times, August 27,
Software Engineering Institute, “Capability Maturity Model Integration (CMMI) Overview”,