Kimon Batoulis

Extracting Decision Logic from Process Models

Although it is not considered good practice, many process models from practice contain detailed decision logic, encoded through control flow structures. This often results in spaghetti-like and complex process models and reduces maintainability of the models. In this context, the OMG proposes to use the Decision Model and Notation (DMN) in combination with BPMN in order to reach a separation of concerns. This paper introduces a semi-automatic approach to (i) identify decision logic in process models, (ii) to derive a corresponding DMN model and to adapt the original process model by replacing the decision logic accordingly, and (iii) to allow final configurations of this result during post-processing. This approach enables business organizations to migrate already existing BPMN models. We evaluate this approach by implementation, semantic comparison of the decision taking process before and after approach application, and an empirical analysis of industry process models.

Integrated process and decision modeling for data-driven processes

While business process models have been proven to represent useful artifacts for organizations, they are not suitable to represent the detailed decision logic underlying processes. Ignoring this limitation often results in complex, spaghetti-like process models for workflows driven by data-based decisions. To avoid this, decision logic should be isolated from process logic, following a separation of concerns paradigm. To support this practice, we present an approach that automatically derives process models for which this paradigm applies. It takes as input structural data-flow relations underlying a workflow and produces a process model that emphasizes the most important decisions in a process, while detailed decision logic is outsourced to dedicated decision models.

Automating data exchange in process choreographies

Communication between organizations is formalized as process choreographies in daily business. While the correct ordering of exchanged messages can be modeled and enacted with current choreography techniques, no approach exists to describe and automate the exchange of data between processes in a choreography using messages. This paper describes an entirely model-driven approach for BPMN introducing a few concepts that suffice to model data retrieval, data transformation, message exchange, and correlation - four aspects of data exchange. For automation, this work utilizes a recent concept to enact data dependencies in internal processes. We present a modeling guideline to derive local process models from a given choreography; their operational semantics allows to correctly enact the entire choreography from the derived models only including the exchange of data. Targeting on successful interactions, we discuss means to ensure correct process choreography modeling. Finally, we implemented our approach by extending the camunda BPM platform with our approach and show its feasibility by realizing all service interaction patterns using only model-based concepts.

Soundness of Decision-Aware Business Processes

With the recent release of the Decision Model and Notation (DMN) specification, standardized decision models can be designed to represent the decisions required for executing business processes. Outsourcing decision logic from process to decision models leads to a separation of concerns and therefore to decision-aware business processes. However, no exhaustive considerations regarding the soundness of the integration of the two types of models have been made so far. Classical soundness checking only looks at the control-flow of a process model. In this paper, we formally define soundness criteria for decision-aware processes that ensure that the process can continue after a decision has been taken, and that all activities following the decision can be executed. A scalable implementation and an analysis of models from participants of an online course on process and decision modeling as well as a from a BPM project of a large insurance company demonstrate the benefits of our contribution.

Automating Data Exchange in Process Choreographies

Process choreographies are part of daily business. While the correct ordering of exchanged messages can be modeled and enacted with current choreography techniques, no approach exists to describe and automate the exchange of data between processes in a choreography using messages. This paper describes an entirely model-driven approach for BPMN introducing a few concepts that suffice to model data retrieval, data transformation, message exchange, and correlation – four aspects of data exchange. For automation, this work utilizes a recent concept to enact data dependencies in internal processes. We present a modeling guideline to derive local process models from a given choreography; their operational semantics allows to correctly enact the entire choreography from the derived models only including the exchange of data. We implemented our approach by extending the camunda BPM platform with our approach and show its feasibility by realizing all service interaction patterns using only model-based concepts.

Enabling Dynamic Decision Making in Business Processes with DMN

While executing business processes, regularly decisions need to be made such as which activities to execute next or what kind of resource to assign to a task. Such a decision-making process is often case-dependent and carried out under uncertainty, yet requiring compliance with organization’s service level agreements. In this paper, we address these challenges by presenting an approach for dynamic decision-making. It is able to automatically propose case-dependent decisions during process execution. Finally, we evaluate it with a use case that highlights the improvements of process executions based on our dynamic decision-making approach.

Automatic Business Process Model Translation with BPMT

Nowadays, many enterprises use business process models for documenting and supporting their operations. As many enterprises have branches in several countries and provide similar services throughout the globe, there is high potential for re-using these process models. However, the language barrier is a major obstacle for the successful re-use of process models, especially in multi-national companies. In this paper, we address this problem by presenting the Business Process Model Translator (BPMT), a technique for the automated translation of business process models that eases the re-use of business process models and reduces redundant work in multi-national companies. It builds upon the state-of-the-art machine translation system Moses and extends it with word and translation disambiguation considering the context of the domain. As a result, the BPMT can successfully deal with the compact and special language fragments that are typically found in business process models. A two-fold evaluation with the BLEU metric and an expert survey showed improvements of our approach over Moses.

Various Notions of Soundness for Decision-Aware Business Processes

The Decision Model and Notation (DMN) specification enables process designers to represent the decision logic and requirements of business processes. When integrating DMN models into processes it needs to be assured that the correctness of the process is not impaired. The precise semantics for executing DMN models in the context of a business process permits to broaden existing soundness notions for workflow verification to encompass such decision-aware processes. This paper presents correctness notions for processes referring to DMN conform decision models and groups them in a manner that follows the intuition of the well established soundness notions for workflow nets. In doing so, we also make use of the different possible states the process can be in at the point at which a decision is made.

REST-Enabled Decision Making in Business Process Choreographies

In the field of business process management, the interaction between business actors or services are modeled via business process choreographies. However, enforcing or implementing business process choreographies is a challenge particularly related to the choreography’s exclusive gateways, which are used to model shared decisions among business actors. Since there is no central locus of control, participants may interpret the data relevant for decision making differently. To tackle this problem, this paper offers a solution by delegating the decision making to a decision service. This service is based on the recently published Decision Model and Notation standard and is provided to the choreography participants via a REST interface. The RESTful decision service assures a correct implementation of choreographies’ exclusive gateways and provides a blueprint for RESTful services that offer decision-making solutions based on the DMN standard.

DMN Decision Execution on the Ethereum Blockchain

Recently blockchain technology has been introduced to execute interacting business processes in a secure and transparent way. While the foundations for process enactment on blockchain have been researched, the execution of decisions on blockchain has not been addressed yet. In this paper we argue that decisions are an essential aspect of interacting business processes, and, therefore, also need to be executed on blockchain. The immutable representation of decision logic can be used by the interacting processes, so that decision taking will be more secure, more transparent, and better auditable. The approach is based on a mapping of the DMN language S-FEEL to Solidity code to be run on the Ethereum blockchain. The work is evaluated by a proof-of-concept prototype and an empirical cost evaluation.