Building software using a microservice architecture is a means that gives more options to scale up applications, deploy them independently and limit their "blast radius" of failure. Microservices tend to solve the complexity and the increasing development problems by applying the functional decomposition principle. This main feature can become a point of weakness in the absence of a fully credible splitting mechanism. One of the main adopted approaches to design services and deal with the boundary identification concern is the Domain Driven Design (DDD). In this paper, we aim to study the efficiency of this approach. We intend to give software architects a full understanding of its capabilities and main limits to be aware of the potential resulting anti-patterns. To this end, we use graph theory to experiment and analyze a reference example, implementing many microservices good practices and patterns. The obtained results show whether if we can rely only on the DDD principles to decompose microservices, or not.

SUMMARY Real‐time applications are those reactive systems whose behavior depends not only on their interactions with the environment but also on the times at which these interactions take place. The timing aspect of such applications makes it hard to test them exhaustively because of the infinite number of possible computations. One way to deal with this difficulty is to have the tester choose some important features of the application and check if they are properly implemented. This paper follows this principle and proposes a method for testing real‐time applications formally modeled as Timed Input Output Automata (TIOA), a variant of Timed Automata of Alur and Dill (Theor. Comp. Sci.1994;126:183–235). The method is based ontest purposes. Atest purposeis a description of a well‐defined testing objective focusing on a single requirement or a set of requirements of the system under test. Test purposes, in this paper, are used to describe the features of the application to be checked by the tester. They are also formally modeled, in this paper, as a TIOA. Since test purposes are a partial behavior of the application under test, they significantly help to reduce the number of test cases to be generated, and consequently minimize the time, effort, and money to spend in testing the application. Basically, the paper proposes an approach, which takes as inputs a test purpose and a specification, and generates test cases, which are able to check if the test purpose is satisfied by an implementation of the specification. The proposed method consists of three main steps. First, the TIOAs of the specification and test purpose are combined together in one TIOA. Second, the resulting TIOA is sampled to construct a sub‐automaton of the system with a finite number of executions for test generation. The sampling of a TIOA is done based on the number of clocks describing the timing behavior of the system. Finally, the sub‐automaton resulting from the second step is traversed to generate test cases. The real‐time applications dealt with in this paper are supposed to be deterministic; i.e. the test results are the same when the same input data are applied to the implementation of the application. Copyright © 2011 John Wiley & Sons, Ltd.

Nowadays, multiagent systems became a widely used technology in everyday life. More studies are needed to evaluate these systems from different aspects such as evaluating agent dialogues, the participants to these dialogues, and the protocols governing the dialogues, etc. In this paper, we define new measures for dialogue games from an external agent's point of view. In particular, two measurement sets are proposed: in the first set, we use Shannon entropy to measure the certainty index of the dialogue. This involves i) using Shannon entropy to measure the agent's certainty about each move during the dialogue; and ii) using Shannon entropy to measure the certainty of the agents about the whole dialogue with two different ways. The first way is by taking the average of the certainty index of all moves, and the second way is by determining all possible dialogues and applying the general formula of Shannon entropy. In the second set, we introduce two metrics: i) measuring the goodness of the agents in the real dialogue (i.e. the dialogue that effectively happened between the participants); and ii) measuring the farness of the agents from the right dialogue (i.e. the best dialogue that can be produced by two agents if they know the knowledge bases of each other). Many dialogue game types have been proposed in multiagent systems. In this paper, we focus on one specific type, namely quantitative negotiation such as bargaining.

Real-time systems interact with their environment using time constrained input/output signals. Examples of real-time systems include patient monitoring systems, air traffic control systems, and telecommunication systems. For such systems, a functional misbehavior or a deviation from the specified time constraints may have catastrophic consequences. Therefore, ensuring the correctness of real-time systems becomes necessary. Two different techniques are usually used to cope with the correctness of a software system prior to its deployment, namely, verification and testing. In this paper, we address the issue of testing real-time software systems specified as a timed input output automaton (TIOA). TIOA is a variant of timed automaton. We introduce the syntax and semantics of TIOA. We present the potential faults that can be encountered in a timed system implementation. We study these different faults based on TIOA model and look at their effects on the execution of the system using the region graph. We present a method for generating timed test cases. This method is based on a state characterization technique and consists of the following three steps: First, we sample the region graph using a suitable granularity, in order to construct a subautomaton easily testable, called grid automaton. Then, we transform the grid automaton into a nondeterministic timed finite state machine (NTFSM). Finally, we adapt the generalized Wp-method to generate timed test cases from NTFSM. We assess the fault coverage of our test cases generation method and prove its ability to detect all the possible faults. Throughout the paper, we use examples to illustrate the various concepts and techniques used in our approach.

Real time reactive systems interact with their environment, using inputs and outputs, within specified time constraints. For such systems, a functional misbehavior or a deviation from the specified time constraints may have catastrophic consequences. Therefore, ensuring the correctness of real time systems becomes very important. We introduce the potential faults which can be encountered in a timed system implementation. We adapt an existing test cases generation technique, based on state characterization set, to generate timed test cases from a timed system specification. We model a timed system with a Timed Input Output Automaton (TIOA), which is a variant of the Alur and Dill model (R. Alur and D. Dill, 1994). In order to generate the timed test suite, the TIOA is first transformed into a Nondeterministic Timed Finite State Machine (NTFSM) with a given granularity. We illustrate our method with an example.