Kelso, from my limited understanding of the asio drivers, these are written by the hardware mfg of sound cards and other interfacing sound hardware. The asio allows for communication between windows and the computer and sound card for the Input and output of audio signals.
The mfg must implement the code that allows for windows and the sequencer or other apps to do computer speak at the binary level. Some of these drivers are better than others but each is linked to the hardware, mostly.
There is one exception that I'm vaguely aware of and that is a program called asio4all but I don't believe it is a true asio driver.
There are several sites that deal with the hardware of sound and one is called
http://www.gearslutz.com/board/
There are others , some others here might have a better take on this.
Wyndham