Outline for November 21, 2003
Reading: Chapter 18.2, 22.1-22.2
The UNIX operating system (and most computer systems) have an
all-powerful user (root or administrator or wheel).
- Why does such a user exist?
- Dennis Ritchie called the existance of this user "both a
theoretical and practical flaw." Why?
- If you were designing an operating system with security being
a key goal, could you avoid creating such a user? If so how? If
not, how would you implement the functionality of the root user?
Outline for the Day
- Life cycle: Waterfall Model
- Requirements definition and analysis
- System and software design (system design, program design)
- Implementation and unit testing
- Integration and system testing
- Operation and maintenance
- Other life cycle models
- Exploratory programming
- Formal transformation
- System assembly from reusable components
- Extreme programming
- Malicious logic
- Quickly review Trojan horses, viruses, bacteria; include
animal and Thompson's compiler trick
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