1. Where Do the 7 layers “fit”? 1 2 3 4 5 6 7 Or, where is the dividing line between hdw & s/w? ? ?

2. Implementing the Model User Space Software OS Space Software Firmware Hardware

3. Some More Definitions User Space Software - Code that executes as any program that a normal user could compile and run OS Space Software - Code that executes on the host CPU but in a mode or with special access that normal users can not use ‘Firmware’ - Code that executes on a processor (special or general purpose) that is different from the host CPU; may be in PROM or RAM downloaded from another source Hardware - Generally special purpose VLSI and analog/linear interface components

4. Assigning the 7 layers Performance vs Flexibility