Contract-based test generation for data flow of business processes using constraint programming

The verification of the properties of a business process (BP) has become a significant research topic in recent years. In the early stages of development, the BP model (e.g. BPMN, EPC), the BP contract (task contract, regulations and laws, business rules), and the test objectives (requirements) are the only elements available. In order to support the modellers, automatic tools must be provided in order to check whether their business processes are in line with the BP contract. This paper proposes a new business process called the automatic test-case generator to automate the generation of test cases and verify that a BP has the intended functionality (semantic conformance). This generator is analysed, designed and implemented by taking into account the following tasks: Annotation of the BP model with the business process contract, calculation of the various data flow paths, transformation of these data flow paths into SSA form, and a modelling of a constraint satisfaction problem (constraint programming) of the BP contract for all data flow paths. The execution of this business process generates the test cases automatically.Junta de Andalucía P08-TIC-04095Ministerio de Ciencia e Innovación TIN2009-1371

Quality of (Digital) Services in e-Government

Internet growth in the nineties supported government ambition to provide better services to citizens through the development of Information and Communication Technologies based solutions. Thanks to the Lisbon conference, which in 2000 covered and investigated this topic, e-government has been recognized as one of the major priorities in Public Administration innovation process. As a matter of\ud fact in the last 10 years the number of services provided to citizens through Information and Communication Technologies has increased rapidly. Nevertheless the increasing rate, the access and usage of digital services do not follow the same trend. Nowadays Public Administrations deliver many electronic services which\ud are seldom used by citizens. Different reasons contribute to the highlighted situation.\ud The main assumption of the thesis is that quality of e-government digital services strongly affects real access to services by citizens. According to the complexity of quality in e-government, one of the main challenges was to define a suitable quality model. To reach such aim, domain-dependent characteristics on the services delivery have been investigated. The defined model refers to citizen,\ud technology and service related quality characteristics. Correspondingly a suitable way to represent, assess, and continuously improve services quality according to\ud such domain requirements has been introduced.\ud Concerning the service related quality aspects a methodology and a tool permitting to formally and automatically assess the quality of a designed service with\ud respect to the quality model has been defined. Starting from an user friendly notation, both for service and quality requirements, the proposed methodology has\ud been implemented as an user friendly tool supported by a mapping from user friendly notations to formal language. The tool allows to verify formally via model checking, if the given service satisfies one by one the quality requirements addressed by the quality model.\ud Additionally in some case an unique view on e-government service quality is quite useful. A mathematical model provides a single value for quality starting from the assessment of all the requirements defined in the quality model. It relies on the following activities: homogeneity, interaction and grouping.\ud A set of experiments has been performed in order to validate the goodness of the work. Services already implemented in a local Public Administration has\ud been considered. Literature review and domain experts knowledge were the main drivers of this work. It proofs the goodness of the quality model, the application of formal techniques in the complex field of study such as e-government and the quality aggregation via the mathematical model.\ud This thesis introduces advance research in e-government by providing the contributions that quality oriented service delivery in Public Administration promotes services used by the citizens. Further applications of the proposed approaches could be investigated in the areas of practical benchmarking and Service Level Agreement specification

A Usage Control Model Extension for the Verification of Security Policies in Artifact-Centric Business Process Models

Artifact-centric initiatives have been used in business processes whose data management is complex, being the simple activity centric workflow description inadequate. Several artifact-centric initia tives pursue the verification of the structural and data perspectives of the models, but unfortunately uncovering security aspects. Security has become a crucial priority from the business and customer perspectives, and a complete verification procedure should also fulfill it. We propose an extension of artifact-centric process models based on the Usage Control Model which introduces mechanisms to specify security policies. An auto matic transformation is provided to enable the verification of enriched artifact-centric models using existing verification correctness algorithms.Ministerio de Ciencia y Tecnología TIN2015-63502-C3-2-

Dynamic adaptation of service compositions with variability models

Web services run in complex contexts where arising events may compromise the quality of the whole system. Thus, it is desirable to count on autonomic mechanisms to guide the self-adaptation of service compositions according to changes in the computing infrastructure. One way to achieve this goal is by implementing variability constructs at the language level. However, this approach may become tedious, difficult to manage, and error-prone. In this paper, we propose a solution based on a semantically rich variability model to support the dynamic adaptation of service compositions. When a problematic event arises in the context, this model is leveraged for decision-making. The activation and deactivation of features in the variability model result in changes in a composition model that abstracts the underlying service composition. These changes are reflected into the service composition by adding or removing fragments of Business Process Execution Language (WS-BPEL) code, which can be deployed at runtime. In order to reach optimum adaptations, the variability model and its possible configurations are verified at design time using Constraint Programming. An evaluation demonstrates several benefits of our approach, both at design time and at runtime.This work has been developed with the support of MICINN under the project everyWare TIN2010-18011 and co-financed with ERDF.Alférez Salinas, GH.; Pelechano Ferragud, V.; Mazo, R.; Salinesi, C.; Díaz, D. (2014). Dynamic adaptation of service compositions with variability models. Journal of Systems and Software. 91:24-47. https://doi.org/10.1016/j.jss.2013.06.034S24479

Combi-BP: automating the data-oriented optimization in business processes. From declarative to executable models.

One of the main objectives of a business expert is to model the business goals of an enterprise process. Several languages have been created to describe the necessary activities to achieve the objective, especially in the business process context. These languages can be divided into imperative and declarative ones. Declarative languages tend to be used when the speci c model is unknown, being possible to describe what has to be done instead of how. Otherwise, imperative languages permit to describe how the things have to be done and then, the imperative models can be executed in any Business Process Management System (BPMS). The declarative descriptions are more exible, since they permit to describe the model in a more relaxed way, which means that various process executions can follow the same declarative description. However, both paradigms are focused on the activities order description, but unfortunately, the data perspective is missed. Furthermore, the optimization of a business goal which depends on the exchanged data during the execution of the business process has not been included in previous proposals. There are no solutions that allow the business experts to describe nor execute a declarative description where the executed model depends on the exchanged data between the involved activities in each instance. In this thesis dissertation, an approach to support this data-oriented optimization in business process is presented. A data-oriented optimization problem is a process whose main purpose is to obtain the best business product. In order to obtain this business product, the process must combine several activities by taking into account the existing data-structure and data-value dependencies. Both kind of dependencies are established by a set of constraints that relate the data (consumed and provided by the activities) and the data given by the customer. Therefore, the BPs under the scope of our research are those which are centred on developing sound data in business processes, analysing how data-structure and data-value dependencies can aect the correct business process execution. However, if the data provided at runtime for the activities that conform the model have not got enough level of quality, then business process will not be successfully executed. The base of the proposal is focused on the combination of the advantages of both paradigms: the exibility of the declaratives, and the automatic execution in a BPMS of the imperatives. On the one hand, we want to describe a exible model using a declarative description where the exchanged data and an optimization objective are included. In the other hand, this declarative model must be executed in a generic business process management system with the aim of support any instance of the process. Therefore, how the declarative description can be transformed into an imperative business process is developed. The transformation methodology that we propose is based on Model-Driven Architecture. Firstly, the declarative is transformed into an imperative which takes into account the data-structure dependencies. The exibility of the declarative speci cation is kept thanks to the use of Constraint Programming. On the other hand, the resulting imperative model is enriched with new intelligent techniques, also based on Constraint Programming, in order to solve the data-value dependencies. Finally, a methodology and an implementation are developed in order to make the business process aware of the data-quality aspects

Quality of process modeling using BPMN: a model-driven approach

Dissertação para obtenção do Grau de Doutor em Engenharia InformáticaContext: The BPMN 2.0 specification contains the rules regarding the correct usage of the language’s constructs. Practitioners have also proposed best-practices for producing better BPMN models. However, those rules are expressed in natural language, yielding sometimes ambiguous interpretation, and therefore, flaws in produced BPMN models. Objective: Ensuring the correctness of BPMN models is critical for the automation of processes. Hence, errors in the BPMN models specification should be detected and corrected at design time, since faults detected at latter stages of processes’ development can be more costly and hard to correct. So, we need to assess the quality of BPMN models in a rigorous and systematic way. Method: We follow a model-driven approach for formalization and empirical validation of BPMN well-formedness rules and BPMN measures for enhancing the quality of BPMN models. Results: The rule mining of BPMN specification, as well as recently published BPMN works, allowed the gathering of more than a hundred of BPMN well-formedness and best-practices rules. Furthermore, we derived a set of BPMN measures aiming to provide information to process modelers regarding the correctness of BPMN models. Both BPMN rules, as well as BPMN measures were empirically validated through samples of BPMN models. Limitations: This work does not cover control-flow formal properties in BPMN models, since they were extensively discussed in other process modeling research works. Conclusion: We intend to contribute for improving BPMN modeling tools, through the formalization of well-formedness rules and BPMN measures to be incorporated in those tools, in order to enhance the quality of process modeling outcomes