On improving efficiency of model checking through systematically ...

transformation procedure indeed takes over one part of the verification that
should be done automatically.
The risk of missing cases increases when the system grows in the sense
that it contains more locations, transitions, and especially parallel processes.
A tool to take over this complicated procedure would help to avoid the errorprone
manual transformation. However, we did not pursue the development
of such a tool.
2.4 Summary
In this chapter we have introduced the specification language to model an
input system for Nbac. Nbac input format is a low-level formal that specifies
dataflow equations on Boolean and integer variables.
There are three ways to obtain an Nbac input model: create the model
directly in Nbac input language, transform manually from an XTG model,
and transform automatically from a Lustre program. We explained the
framework to construct an Nbac input model from an XTG model using the
Fischer’s protocol example as an illustration. Although the model of Fischer’s
protocol is simple, the manual construction procedure still requires a
large amount of work.
We found that the aforementioned manual procedure to contruct an Nbac
input model is an error-prone procedure. For example, in a system with a
significant number of parallel processes, it is very likely that we will overlook
a few cases. A tool to take over this part which has not yet been developed
at the moment is indispensable.
In the next chapter, we move to an important part of our project: develop
a tool serving as a bridge to connect Nbac and PMC/Uppaal.
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