Since the structure of a QPN is defined by a CPN, it is obvious to exploit properties of the CPN especially for the qualitative analysis of the QPN. PN theory offers a variety of analysis algorithms and for special cases very efficient algorithms are known. So, provided the underlying CPN satisfies a property, we are interested to prove that the QPN in turn also satisfies this property. It is known that this is not the case for general QPNs . But, restricting the QPN's structure and/or type of queues, properties of the CPN are passed on the QPN. To be applicable such restrictions must by themselves be efficient to verify. The next subsections will discuss restrictions for ensuring boundedness and liveness. The existence of home states is touched on in the last subsection.