Change Propagation in Collaborative Processes Scenarios

Process flexibility and change constitute major challenges for process-aware information systems. This does not only hold for centralized process scenarios, but also for collaborative ones involving multiple distributed and autonomous partners. If one partner adapts its private process, the applied change might affect the processes of the other partners as well. Hence the change must be propagated to concerned partners in a transitive way. A fundamental challenge is then to find ways of propagating the changes in a decentralized manner. Existing approaches dealing with changes of collaborative processes are limited with respect to the change operations considered and their dependency on certain process specification languages. By contrast, this paper presents a generic change propagation approach based on the Refined Process Structure Tree. Our approach is applicable independently of a particular process specification language. Further, it considers a comprehensive set of change patterns. Finally, it is shown that the provided change propagation algorithms preserve structural dependencies for any change pattern

Toward synchronization between decentralized orchestrations of Composite Web Services

International audienceWeb service paradigm and related technologies have provided favorable means for the realization of collaborative business processes. From both conceptual and implementation points of view, the business processes are based on a centralized management approach. Nevertheless, it is very well known that the enterprise-wide process management where processes may span multiple organizational units requires particular considerations on scalability, heterogeneity, availability and privacy issues, that in turn, require particular consideration on decentralization. In a previous work , we have described a flexible methodology for splitting a centralized process specification into a form that is amenable to a distributed execution. The approach is based on the computation of very basic dependencies between process elements. In this paper, we extend this approach to support advanced patterns such as Loops, Multiple instances and Discriminator, and incorporate the necessary synchronization between the different processing entities. We also detail our interconnection mechanism and explain how to handle control and data dependencies between activities of the different partitions through asynchronous message exchanges. The proposed methodology preserves semantics of the centralized process with a peer-to peer interactions among the derived decentralized processes

Dealing with change in process choreographies: Design and implementation of propagation algorithms

Enabling process changes constitutes a major challenge for any process-aware information system. This not only holds for processes running within a single enterprise, but also for collaborative scenarios involving distributed and autonomous partners. In particular, if one partner adapts its private process, the change might affect the processes of the other partners as well. Accordingly, it might have to be propagated to concerned partners in a transitive way. A fundamental challenge in this context is to find ways of propagating the changes in a decentralized manner. Existing approaches are limited with respect to the change operations considered as well as their dependency on a particular process specification language. This paper presents a generic change propagation approach that is based on the Refined Process Structure Tree, i.e., the approach is independent of a specific process specification language. Further, it considers a comprehensive set of change patterns. For all these change patterns, it is shown that the provided change propagation algorithms preserve consistency and compatibility of the process choreography. Finally, a proof-of-concept prototype of a change propagation framework for process choreographies is presented. Overall, comprehensive change support in process choreographies will foster the implementation and operational support of agile collaborative process scenarios

Communications semantics for WSBPEL Processes

ISBN : 978-0-7695-3310-0International audienceWSBPEL opens up the possibility of applying a range of formal techniques to the verification of Web service behaviors from two points of view: constraints between activities within the same process and dependencies between activities of different processes. In a previous work, we have described an approach for the verification of Web service compositions defined by a set of BPEL processes. The key aspect of such a verification task is the model adopted for representing the communications among the services participating to the composition. In this paper, we propose to extend this approach to handle dependencies between activities of different process orchestrations through message exchanges. Our aim is to enable supporting models of service choreography with multiple interacting Web services compositions, from the perspective of a collaborative distributed composition development environment. The process of behavior analysis moves from a single local process to that of modelling and analyzing the behavior of multiple processes across composition domains

User-Perceived Privacy in Blockchain

This paper studies users’ privacy perceptions of UTXO-based blockchains such as Bitcoin. In particular, it elaborates -- based on interviews and questionnaires -- on a mental model of employing privacy-preserving techniques for blockchain transactions. Furthermore, it evaluates users\u27 awareness of blockchain privacy issues and examines their preferences towards existing privacy-enhancing solutions, i.e., add-on techniques to Bitcoin versus built-in techniques in privacy coins. Using Bitcoin as an example, we shed light on existing discrepancies between users\u27 privacy perceptions and preferences as well as current implementations

Change and Compliance in Collaborative Processes

During their lifecycle, business processes are keen to change. Changes either concern the process model structure or the accompanying rules; e.g. compliance rules (laws and regulations). In the context of business process collaborations, several process partners collaborate together, and changing one process might result in knock-on effects on the other processes; i.e., change propagation. Since business processes are often subject to restrictions that stem from laws, regulations or guidelines; i.e., compliance rules, changing them might lead to the violations of these rules (non-compliability). So far, only the impacts of process changes in choreographies have been studied. In this work, we propose an approach that analyzes and evaluates the impacts of process changes on the different compliance rules and inversely, the impacts of compliance rule changes on the process choreography

Decomposition-based Verification of Global Compliance in Process Choreographies

The verification of global compliance rules (GCR) in process choreographies (e.g., partner-spanning quality assurance in supply chains) is crucial and challenging due to the restricted visibility of the private processes of the collaborating partners. This paper provides a novel algorithm that decomposes global compliance rules into assertions that can be verified by the partners in a distributed way without revealing any private process details. The decomposition is based on transitivity properties of the underlying GCR specification. This work uses GCR based on antecedent and occurrence patterns and illustrates the transitivity properties based on their specification in first order predicate logic. It is formally shown that the original GCR can be reconstructed from the assertions, which ensures the viability of the approach. The algorithms are prototypically implemented and applied to several scenarios. The ability of checking global compliance constitutes a fundamental pillar of any approach implementing process choreographies with multiple partners