FOCLASA 2015

14th International Workshop on Foundations of

Coordination Languages and Self-Adaptive Systems

5 Sep 2015, Madrid, Spain
Co-located with CONCUR'15

Modern software systems are distributed, concurrent, mobile, and often involve composition of heterogeneous components and stand-alone services. Service coordination and self-adaptation constitute the core characteristics of distributed and service-oriented systems. Coordination languages and formal approaches to modelling and reasoning about self-adaptive behaviour help to simplify the development of complex distributed service-based systems, enable functional correctness proofs and improve reusability and maintainability of such systems.

FOCLASA 2015 is a workshop collocated with the 26th International Conference on Concurrency Theory. The goal of the FOCLASA workshop is to put together researchers and practitioners of the aforementioned fields, to share and identify common problems, and to devise general solutions in the context of coordination languages and self-adaptive systems.

Registration

Registration is now open through the official CONCUR website. Attention: early registration ends on June 24th, quickly after the notification date.

Contact

For any further information please contact the FOCLASA 2015 PC Chairs.

Tweets

Topics of Interest

Topics of interest include (but are not limited to):

  • Theoretical models and frameworks for component and service coordination, service composition, service adaptation and concurrent system modeling.
  • Applications and usability studies for the aforementioned theoretical models, interaction and coordination challenges in various application domains.
  • Languages and specification protocols for component and service interaction, their semantics, expressiveness, validation and verification, type checking, static and dynamic analysis.
  • Software as a service models (e.g., cloud computing) and dynamic software architectures, such as self-adaptive and self-organizing systems.
  • Service composition and coordination for Future Internet applications, service orchestration and choreographies, related theories and methods, and possible model-driven development approaches.
  • Tools and environments for the development of concurrent and customizable self- monitoring, self-adaptive and self-organizing applications.
  • Algorithms, mathematical models and realization frameworks for quality-of-service observation, storage, history-based analysis in self-adaptive systems (queuing models, load balancing, fault-tolerance analysis, machine learning systems).

In particular, practice, experience and methodologies from the following areas are solicited as well:

  • Business process modeling
  • Cloud computing
  • Service-oriented computing
  • Component-based systems
  • Grid computing
  • Large-scale distributed systems
  • Multi-agent systems
  • Networked embedded systems
  • Peer-to-peer systems

Survey works analysing and comparing literature on the topics of FOCLASA are also welcome.

Call for Papers Download in PDF PDF

FOCLASA 2015 is a workshop colocated with the 26th International Conference on Concurrency Theory (CONCUR 2015). The goal of the FOCLASA workshop is to put together researchers and practitioners to share and identify common problems, and to devise general solutions in the context of coordination languages and self-adaptive systems.

Important Dates

  • June 17th 24st, 2015: Deadline for abstract submission
  • June 19th 26th, 2015: Deadline for paper submission
  • July 20th, 2015: Notifications
  • August 3rd, 2015: Final versions

Submissions must describe authors' original research work and their results. Description of work-in-progress with concrete results is also encouraged. The contributions should not exceed 15 pages in the EPTCS style (http://style.eptcs.org/) and should be submitted as Portable Document Format (PDF) files using the EasyChair submission site:

Submitting an abstract does not put any obligation on the authors to submit a full paper. Abstracts without an accompanying full paper by the paper submission deadline are automatically considered withdrawn. The authors are, however, encouraged to explicitly withdraw their abstract, if they decide not to submit a full paper. All submissions will be reviewed by an international program committee who will make a selection among the submissions based on the novelty, soundness and applicability of the presented ideas and results.

Concurrent submissions to WS-FM/BEAT (a CONCUR co-located event - International Symposium on Web Services, Formal Methods and Behavioural Types) and FOCLASA are allowed for those papers that may potentially enhance both venues. Authors of such double submissions should identify them to the Program Chairs at the time of submission (by choosing the "Regular paper submitted also to WS-FM/BEAT” category in the FOCLASA EasyChair site). Reviews may be shared between WS-FM/BEAT and FOCLASA. Submissions accepted by WS-FM/BEAT will be considered automatically withdrawn from FOCLASA. Concurrent submission to other venues (conferences, workshops or journal) and submission of papers under consideration elsewhere are not allowed.

A printed version of the proceedings will be distributed among participants during the workshop. The proceedings of the workshop will be published as a separate volume. Participants will give a presentation of their papers in twenty minutes, followed by a ten-minute round of questions and discussion on participants' work. Following the tradition of the past editions, we plan to have a special issue of an international scientific journal devoted to FOCLASA 2015. Selected participants will be invited to submit an extended version of their papers after the workshop. These extended versions will be reviewed by an international program committee, which will decide on their final publication on the special issue. In the last few editions of FOCLASA, a special issue of Science of Computer Programming has been dedicated to this workshop.

Workshop Program

This year FOCLASA and WS-FM/BEAT will have a joint program.
This page describes only the program for Sep 5, when the talks for FOCLASA occur. The more general program for WS-FM/BEAT and FOCLASA can be found in WS-FM/BEAT's website.

08:50 - Opening
09:00 - Session 1

Context-Oriented programming languages provide us with primitive constructs to adapt program behaviour depending on the evolution of their operational environment, namely the context. In previous work we proposed MLCoDa, a context-oriented language with two-components: a declarative constituent for programming the context and a functional one for computing. This paper describes the implementation of MLCoDa as an extension of F#.

Programmers often code up asynchronous message-passing systems as communicating finite-state actors. An actor in some state listens for messages, responds to those messages, and transitions to another state. Most of these systems allow messages to carry actor addresses.

This paper presents a kernel language for implementing and specifying such systems. A specification consists of finite-state machines, expressing what kind of messages each component should expect and what kind of actions it should take in response. In addition, a specification may prescribe how a component may use an address received from a message as well as how a component handles inputs on addresses that it sends out. Finally, a conformance relation articulates when an implementation meets such a specification.

10:30 - Break
11:00 - Session 2

The Future Internet is becoming a reality, providing a large-scale computing environments where a virtually infinite number of available services can be composed so to fit users’ needs. Modern service-oriented applications will be more and more often built by reusing and assembling distributed services. A key enabler for this vision is then the ability to automatically compose and dynamically coordinate software services. Service choreographies are an emergent Service Engineering (SE) approach to compose together and coordinate services in a distributed way. When mismatching third-party services are to be composed, obtaining the distributed coordination and adaptation logic required to suitably realize a choreography is a non-trivial and error prone task. Automatic support is then needed. In this direction, this paper leverages previous work on the automatic synthesis of choreography-based systems, and describes our preliminary steps towards exploiting Enterprise Integration Patterns to deal with a form of choreography adaptation.

We survey our work on choreographies and behavioural contracts in multiparty interactions. In particular theories of behavioural contracts are presented which enable reasoning about correct service composition (contract compliance) and service substitutability (contract refinement preorder) under different assumptions concerning service communication: synchronous communication with patient non-preemptable or impatient invocations, or asynchronous communication. Correspondingly, relations concerning behavioural contracts and choreographic descriptions are considered, where a contract for each communicating party is, e.g., derived by projection.

Contract refinement relations are induced as the maximal preoders which preserve contract compliance and global traces. The obtained preorders are then characterized in terms of a new form of testing, called compliance testing (where not only tests must succeed but also the system under test), and compared with classical preorders. Moreover, recent work about adaptable choreographies and behavioural contracts is presented, where the theory above is extended to update mechanisms allowing choreographies/contracts to be modified at run-time by internal (self-adaptation) or external intervention.

13:00 - Lunch
14:45 - Session 3
16:00 - Break
16:30 - Session 4

Originated in collaborative editors, Operational Transformation (OT) is an optimistic replication technique which allows many users to concurrently update the shared data and exchange their updates in any order since the consistency of all replicas, i.e. the fact that all users view the same data, is ensured in all cases. OT enforces out-of-order execution of concurrent updates using transformation functions that must have been planned in advance.

Undoing operations is an indispensable feature for many collaborative applications mainly collaborative editors. It provides the ability to restore a correct state of the shared data after erroneous operations. In particular, selective undo allows users to undo any operation and is based on rearranging operations in the history using the OT approach. For preserving the data consistency, it is a challenging task how to meaningfully combine OT and undo approaches. Even though various undo solutions have been proposed over the recent years, they are either limited or erroneous.

In this paper, we propose a constraint-based approach to address the undo problem that is formulated as a Constraint Satisfaction Problem (CSP) for generating all consistent and undoable transformation functions for any shared object altered by a set of primitive operations. By using CSP approach, we are able to analyze all covered transformation cases for objects with finite size of operations and to study the relation between the commutativity and the undoability. This enables us to state a very important theoretical result since we prove that commutativity is necessary and sufficient to achieve undoability for small set of operations (of sizes 2 and 4) and only sufficient otherwise. This work represents a step forward toward a practical use of CSP techniques for designing safe OT-based collaborative applications.

We propose the use of structured natural language (English) in specifying service choreographies, focusing on the what rather than the how of the required coordination of participant services in realising a business application scenario. The declarative approach we propose uses the OMG standard Semantics of Business Vocabulary and Rules (SBVR) as a modelling language. The service choreography approach has been proposed for describing the global orderings of the invocations on interfaces of participant services. We therefore extend SBVR with a notion of time which can capture the coordination of the participant services, in terms of the observable message exchanges between them. The extension is done using existing modelling constructs in SBVR, and hence respects the standard specification. The idea is that users - domain specialists rather than implementation specialists - can verify the requested service composition by directly reading the structured English used by SBVR. At the same time, the SBVR model can be represented in formal logic so it can be parsed and executed by a machine.

18:00 - Closing

Keynote talk

Towards Dynamic Updates in Service Composition

We survey our work on choreographies and behavioural contracts in multiparty interactions. In particular theories of behavioural contracts are presented which enable reasoning about correct service composition (contract compliance) and service substitutability (contract refinement preorder) under different assumptions concerning service communication: synchronous communication with patient non-preemptable or impatient invocations, or asynchronous communication. Correspondingly, relations concerning behavioural contracts and choreographic descriptions are considered, where a contract for each communicating party is, e.g., derived by projection.

Contract refinement relations are induced as the maximal preoders which preserve contract compliance and global traces. The obtained preorders are then characterized in terms of a new form of testing, called compliance testing (where not only tests must succeed but also the system under test), and compared with classical preorders. Moreover, recent work about adaptable choreographies and behavioural contracts is presented, where the theory above is extended to update mechanisms allowing choreographies/contracts to be modified at run-time by internal (self-adaptation) or external intervention.

About the speaker

Mario Bravetti

Mario Bravetti is an Associate Professor (with national Full Professor habilitation) at the Computer Science and Engineering Department of University of Bologna. He is also member of the FOCUS (FOundations of Component-based Ubiquitous Systems) team which is part of the INRIA Sophia Antipolis - Méditerranée research center. He he is co-founder and member of the steering committee of the international workshop on Web Services and Formal Methods (WS-FM). He has been organizer/program committee chair of several international conferences and events, such as the 11th International Conference on Software Engineering and Formal Methods (SEFM 2013), the 20th International conference on Concurrency Theory (CONCUR 2009), and the meeting on the 25th anniversary of Process Algebra. His current research interests include behavioural contracts for service composition.

Program Committee Chairs

Program Committee

  • Farhad Arbab, CWI, The Netherlands
  • Marco Autili, Univ. of L'Aquila, Italy
  • Luís Barbosa, Universidade do Minho, Portugal
  • Steffen Becker, University of Paderborn, Germany
  • Javier Cámara, Carnegie Mellon University, USA
  • Carlos Canal, University of Malága, Spain
  • Carlos Cuesta, Rey Juan Carlos University, Spain
  • David Garlan, Carnegie Mellon University, USA
  • Alfredo Goldmann, University of São Paulo, Brazil
  • Keijo Heljanko, Aalto University, Finland
  • Jean-Marie Jacquet, University of Namur, Belgium
  • Christian Krause, SAP Innovation Center, Germany
  • Sun Meng, Peking University, China
  • Liliana Pasquale, University of Limerick, Ireland
  • José Proença, iMinds-Distrinet and HASLab/INESC TEC, KU Leuven, Belgium
  • Marjan Sirjani, Reykjavik University, Iceland
  • Carolyn Talcott, SRI International, USA
  • Massimo Tivoli, University of L'Aquila, Italy
  • Mirko Viroli, University of Bologna, Italy

Steering Committee

  • Farhad Arbab, CWI, The Netherlands
  • Antonio Brogi, University of Pisa, Italy
  • Carlos Canal, University of Málaga, Spain
  • Jean-Marie Jacquet, University of Namur, Belgium
  • Ernesto Pimentel, University of Málaga, Spain
  • Gwen Salaün, Grenoble INP - INRIA Grenoble - LIG, France

Publicity Chair

  • Alexander Perucci, University of L'Aquila, Italy