3 research outputs found
Constraint-based oracles for timed distributed systems
© 2017, IFIP International Federation for Information Processing. This paper studies the situation in which the system under test and the system model are distributed and have the same structure; they have corresponding remote components that communicate asynchronously. In testing, a component with interface C i has its own local tester that interacts with C i and this local tester observes a local trace consisting of inputs, outputs and durations as perceived by C i . An observation made in testing is thus a multi-trace: a tuple of (timed) local traces, one for each C i . The conformance relation for such distributed systems combines a classical unitary conformance relation for localised components and the requirement that the communication policy was satisfied. By expressing the communication policy as a constraint satisfaction problem, we were able to implement the computation of test verdicts by orchestrating localised off-line testing algorithms and the verification of constraints defined by message passing between components. Lastly, we illustrate our approach on a telecommunications system
Symbolic Path-guided Test Cases for Models with Data and Time
This paper focuses on generating test cases from timed symbolic transition
systems. At the heart of the generation process are symbolic execution
techniques on data and time. Test cases look like finite symbolic trees with
verdicts on their leaves and are based on a user-specified finite symbolic path
playing the role of a test purpose. Generated test cases handle data involved
in time constraints and uninitialized parameters, leveraging the advantages of
symbolic execution techniques
A small-step approach to multi-trace checking against interactions
Interaction models describe the exchange of messages between the different
components of distributed systems. We have previously defined a small-step
operational semantics for interaction models. The paper extends this work by
presenting an approach for checking the validity of multi-traces against
interaction models. A multi-trace is a collection of traces (sequences of
emissions and receptions), each representing a local view of the same global
execution of the distributed system. We have formally proven our approach,
studied its complexity, and implemented it in a prototype tool. Finally, we
discuss some observability issues when testing distributed systems via the
analysis of multi-traces.Comment: long version - 26 pages (23 for paper, 2 for bibliography, and a 1
page annex) - 15 figures (1 in annex