What’s the difference between installing an application and running it in a VAA?

Normally, when you install an application – for example, SQL Server – it makes changes to registry settings and introduces new services.  What we do at AppZero is watch all of that and take those items – registry items, configuration items, and program files – and capture them in a VAA.  Once this is accomplished, that VAA including the application, program and data files, and configuration items can be separated away from the OS into a single file, ready to be copied and run, rather than installed.

The application runs as usual, unaware that it is executing within the context of its VAA.  Any changes it makes are written to the VAA, leaving the underlying OS unchanged.