Hypothesis for an Engineering Oriented Research Thesis

The hypothesis-model is good for research where you want to understand how something works, but I think it is ill-suited for capturing the full scope of engineering research. After all, in engineering, you're primary goal is not to learn something about how the world works, but rather to change how the world works! So, instead of a hypothesis on how something works, I'd put up existing gaps in the ability to do something as a working basis. That will then put a focus on your research result as an extension of technical capabilities. In order to evaluate your research results, you would then have to show that your results actually close the existing gap.

Of course, also engineering research needs to understand something about how existing things work in order to be able to create something new. Hypotheses are suitable in engineering to clarify these preliminary things. In your case, you state that "the existing 'role-based access control' of MS-Windows does not solve some problems" - that sounds like a perfect hypothesis to test for. But verifying this hypothesis is certainly not the key step in your research, and maybe it has already been done previously. That's why I'd recommend not to focus on a hypothesis as the basis for engineering research (though one might use them to clarify preliminaries), but focus on identified gaps in current technical abilities.

Effectively, what you are doing is development of existing research, rather than designing something de novo. The notion of a research hypothesis is therefore somewhat inappropriate to such work, and you wouldn't write a paper describing this work specifying a definitive "hypothesis."

Instead, you'd write the paper emphasizing that your model does something "better," "faster," "more securely," or specifying whatever other accomplishments advance your work from the previous state of affairs. Your thesis should then show how that is accomplished, and give some evidence thereof.