Omparative study of security in Windows and Linux

I need a comparative study of Windows and Linux, specifically their respective security features. This should be divided into three categories: internal threats, outside threats and authority levels.

The following structure should be used:

1. Introduction
2. Internal threats
2.1. Windows
2.2. Linux
3. External threats
3.1. Windows
3.2. Linux
4. Authority levels
4.1. Windows
4.2. Linux
5. Conclusions

If relevant, please cite Operating System Concepts with Java, 7th ed, 2007. ISBN: 9780471769071″, but I also need other sources referenced.

Under 2.2, Linux internal threats, SELinux must be mentioned as one method with which Linux works with security.