Lifted structural invariant analysis of Petri net product lines

Petri nets are commonly used to represent concurrent systems. However, they lack support for modelling and analysing system families, like variants of controllers, different variations of a process model, or the possible configurations of a flexible assembly line. To facilitate modelling potentially large collections of similar systems, in this paper, we enrich Petri nets with variability mechanisms based on product line engineering. Moreover, we present methods for the efficient analysis of the place and transition invariants in all defined versions of a Petri net. Efficiency is achieved by analysing the system family as a whole, instead of analysing each possible net variant separately. For this purpose, we lift the notion of incidence matrix to the product line level, and rely on constraint solving techniques. We present tool support and evaluate the benefits of our techniques on synthetic and realistic examples, achieving in some cases speed-ups of two orders of magnitude with respect to analysing each net variant separatelyThis work has been funded by the Spanish Ministry of Science (PID2021-122270OB-I00) and the R&D programme of Madrid (P2018/TCS-4314

Automated test case generation for the Paxos single-decree protocol using a Coloured Petri Net model

Implementing test suites for distributed software systems is a complex and time-consuming task due to the number of test cases that need to be considered in order to obtain high coverage. We show how a formal Coloured Petri Net model can be used to automatically generate a suite of test cases for the Paxos distributed consensus protocol. The test cases cover both normal operation of the protocol as well as failure injection. To evaluate our model-based testing approach, we have implemented the Paxos protocol in the Go programming language using the quorum abstractions provided by the Gorums framework. Our experimental evaluation shows that we obtain high code coverage for our Paxos implementation using the automatically generated test cases.publishedVersio