The difference between Win Vista and XP driver strategy

Since Windows NT, Microsoft put the device driver in an important position, and began to classify the driver strategy. For example, XP system adopts a three-layer driver strategy: Original package driver, the highest priority. 2. Windows Hardware Quality Labs (WHQL) certified driver, the second priority. 3. Unsigned driver, requires user approval after installation or even directly banned. Windows Vista? It drives Further subdivision, full of seven levels. Windows Vista's grading strategy is as follows: 1. Microsoft WHQL certified driver 2. Microsoft certified original package driver (NT Build Lab Certified). 3. Microsoft signed Windows Sustained Engineering certified driver 4 Signed driver (Enterprise CA). 5. Signed driver (Class 3 CA Certified). 6. Signed driver (MAKECERT.EXE Certified). 7. Microsoft WHQL certified previous version of the operating system driver 8. Unsigned Driver.