Computer Science 322
Operating Systems

Lecture 32: Protection and Security
Date: Friday, May 2, 2008

Announcements
- Final exam administrative details
Final project status
- right here, Monday evening for final project presentations
- open to the public!
Final lecture assignment recap
Security
- What is a secure system? It should not allow:
  - unauthorized reading of information
  - unauthorized modification of information
  - unauthorized destruction of data
  - unauthorized use of resources
  - denial of service for authorized uses
- Authentication: indentifying users to the system
  - most common: passwords, but many ways to steal
  - can have one-time passwords
  - something you know, something you have
  - biometrics
- Threats: how can a security system be compromised?
  - trojan horses
  - trap doors
  - stack/buffer overflows
  - worms/viruses
  - denial of service
- What's better for security, open or proprietary systems?
Course evaluations