Bernd J. Krämer

Service-Oriented Computing – ICSOC 2007

Research Track Full Papers.- Pattern Based SOA Deployment.- A Domain-Specific Language for Web APIs and Services Mashups.- BPEL4Job: A Fault-Handling Design for Job Flow Management.- Faster and More Focused Control-Flow Analysis for Business Process Models Through SESE Decomposition.- Discovering Service Compositions That Feature a Desired Behaviour.- An Hybrid, QoS-Aware Discovery of Semantic Web Services Using Constraint Programming.- Architectural Decisions and Patterns for Transactional Workflows in SOA.- Bite: Workflow Composition for the Web.- Stochastic Modeling of Composite Web Services for Closed-Form Analysis of Their Performance and Reliability Bottlenecks.- SLA-Based Advance Reservations with Flexible and Adaptive Time QoS Parameters.- Monitoring the QoS for Web Services.- Q-Peer: A Decentralized QoS Registry Architecture for Web Services.- Business Process Regression Testing.- Auditing Business Process Compliance.- Specification and Verification of Artifact Behaviors in Business Process Models.- Improving Temporal-Awareness of WS-Agreement.- Maintaining Data Dependencies Across BPEL Process Fragments.- Supporting Dynamics in Service Descriptions - The Key to Automatic Service Usage.- Grid Application Fault Diagnosis Using Wrapper Services and Machine Learning.- Stochastic COWS.- Service License Composition and Compatibility Analysis.- Dynamic Requirements Specification for Adaptable and Open Service-Oriented Systems.- High Performance Approach for Multi-QoS Constrained Web Services Selection.- Negotiation of Service Level Agreements: An Architecture and a Search-Based Approach.- Byzantine Fault Tolerant Coordination for Web Services Atomic Transactions.- Syntactic Validation of Web Services Security Policies.- An Agent-Based, Model-Driven Approach for Enabling Interoperability in the Area of Multi-brand Vehicle Configuration.- User-Driven Service Lifecycle Management - Adopting Internet Paradigms in Telecom Services.- Run-Time Monitoring for Privacy-Agreement Compliance.- Task Memories and Task Forums: A Foundation for Sharing Service-Based Personal Processes.- Research Track Short Papers.- Addressing the Issue of Service Volatility in Scientific Workflows.- Facilitating Mobile Service Provisioning in IP Multimedia Subsystem (IMS) Using Service Oriented Architecture.- eServices for Hospital Equipment.- Using Reo for Service Coordination.- A Context-Aware Service Discovery Framework Based on Human Needs Model.- Weight Assignment of Semantic Match Using User Values and a Fuzzy Approach.- Grounding OWL-S in SAWSDL.- A Declarative Approach for QoS-Aware Web Service Compositions.- Supporting QoS Negotiation with Feature Modeling.- A Multi-criteria Service Ranking Approach Based on Non-Functional Properties Rules Evaluation.- A Development Process for Self-adapting Service Oriented Applications.- Automated Dynamic Maintenance of Composite Services Based on Service Reputation.- Verifying Temporal and Epistemic Properties of Web Service Compositions.- Industrial Track Full Papers.- Research and Implementation of Knowledge-Enhanced Information Services.- A Model and Rule Driven Approach to Service Integration with Eclipse Modeling Framework.- Semantic Web Services in Action - Enterprise Information Integration.- Policy Based Messaging Framework.- Contextualized B2B Registries.- Bridging Architectural Boundaries Design and Implementation of a Semantic BPM and SOA Governance Tool.- SOA and Large Scale and Complex Enterprise Transformation.- Run-Time Adaptation of Non-functional Properties of Composite Web Services Using Aspect-Oriented Programming.- Software as a Service: An Integration Perspective.- Building Data-Intensive Grid Applications with Globus Toolkit - An Evaluation Based on Web Crawling.- QoS-Aware Web Service Compositions Using Non-intrusive Policy Attachment to BPEL.- Execution Optimization for Composite Services Through Multiple Engines.- Service Design Process for Reusable Services: Financial Services Case Study.- Demo Track Short Papers.- UMM Add-In: A UML Extension for UN/CEFACTs Modeling Methodology.- 4 - A Prototype Demonstrating ontext and olicies for ransactional eb ervices.- WSQoSX - A QoS Architecture for Web Service Workflows.- ReoService: Coordination Modeling Tool.

Leveraging web-services and peer-to-peer networks

Peer-oriented computing is an attempt to weave interconnected machines into the fabric of the Internet. Service-oriented computing (exemplified by web-services), on the other hand, is an attempt to provide a loosely coupled paradigm for distributed processing. In this paper we present an event-notification based architecture and formal framework towards unifying these two computing paradigms to provide essential functions required for automating e-business applications and facilitating service publication, discovery and exchange.

Policy definition language for automated management of distributed systems

The heterogeneity, increasing size and complexity of distributed systems requires new architectures, strategies, and tools for their technical management. In this paper we propose a policy based approach to distributed systems management. The use of different abstraction levels allows a stepwise refinement from an informal strategic level to a formalized operational level. On the lowest level, we use a formal language for separate definition of policies and events, that enables the computer to check the syntax of a given policy description and to translate policies into executable rules. To increase the capability for reasoning on a given set of policies, we extended the architecture by a graph model of the process semantics of operational policy and event specifications. The graph model is supported by a compiler mapping operational specifications into their semantic graphs, and performing analysis and manipulation functions on such graphs.

A database model for object dynamics

Due to a technical error, some figures of the above paper were not reproduced satisfactorily. They are printed again below:

Predictable Component Architectures Using Dependent Finite State Machines

The software architect is concerned with both functional and non-functional design. An important task in functional design is the adaptation of a component’s provided interface for use by other components. In non-functional analysis the focus is rather on the prediction and reasoning about reliability and performance properties. We present a method for automatic adaptation, based upon parameterised contracts. This concept extends the notion of design-by-contract from precondition, postcondition and invariant assertions on objects to dynamic protocol descriptions for required and provided interfaces of components. We introduce a novel state machine based model, called dependent finite state machines (DFSMs), and show how DFSMs provide a natural framework for both automatic component adaptation and computational reasoning about timing properties of components and architectures. We use the well-known production cell example for demonstrating our architectural description language.

Compositional semantics of a real-time prototyping language

The formal semantics of a prototyping language for hard real-time systems, PSDL, is given. PSDL provides a data flow notation augmented by application-orientation timing and control constraints to describe a system as a hierarchy of networks of processing units communicating via data streams. The semantics of PSDL are defined in terms of algebraic high-level Petri nets. This formalism combines algebraic specifications of abstract data types with process and concurrency concepts of Petri nets. Its data abstraction facilities are used to define the meaning of PSDL data types, while high-level Petri nets serve to model the casual and timing behavior of a system. The net model exposes potential concurrency of computation and makes all synchronization needs implied by timing and control constraints explicit and precise. Time is treated as state of clocks, and clocks are modeled as ordinary system components. The net semantics provides the basis for applying analysis techniques and semantic tools available for high-level Petri nets. >

Automated verification of function block-based industrial control systems

Abstract The international standard IEC 61131-3, which supports Brad Cox’ concept of “Software-ICs” for industrial control programming, is increasingly being used in safety-related application domains. They include safety-instrumented functions, such as burner management, emergency shutdown and gas leak detection, but also complex automation processes controlling, e.g., chemical production plants. For such highly dependable applications, code inspection and testing, the predominant quality assurance techniques used in practice today, are, in general, not sufficient to demonstrate the functional correctness and safety of an application. This paper presents a theorem prover-based verification technique as a supplementary validation measure. The verification task is separated into the a priori verification of reusable function blocks, which are usually maintained in domain-specific libraries, and a separate compositional proof of individual application programs. Core concepts of the standardized languages, their semantic embedding into higher order logic, and the verification approach are illustrated with a small example. Some design ideas for a verification tool usable by automation engineers and safety licensing authorities conclude the contribution.

Achieving high integrity of process control software by graphical design and formal verification

The International Electrotechnical Commission is currently standardising four compatible languages for designing and implementing programmable logic controllers (PLCs). The language family includes a diagrammatic notation that supports the idea of software ICs to encourage graphical design techniques and systematic software reuse. This paper presents an interactive system with a graphical interface for constructing and validating PLC software. The semantics of a graphical design is defined by a mapping associating each design with an executable formal specification. The specification provides the basis for rigorous proofs and early tests of critical properties of a new design. A realistic example illustrates these features.

Languages for the specification of software

Abstract A variety of specification languages exist that support one or more phases of software development. This article emphasizes languages that support the functional phase, i.e., languages that can be used to define the observable behavior of a system. The languages surveyed include Z, Prolog, SF, Clear, Larch, PAISLey, Spec, CSP, SEGRAS and BagL. The article divides the languages into four major categories based on the way the language specifies the external behavior of the system and on the ability of the language to specify concurrent systems. Each language section includes a discussion of the constructs of the language, a specification of a problem in the language, and an evaluation of the language. The article is intended to acquaint the reader with a wide range of functional specification languages.

On a rule based management architecture

The paper describes a hybrid approach towards distributed systems management. In our distributed environment the management policies are represented by rules. Interpretation of the rules and automated activation of appropriate management tools is done by the software development environment Marvel. Rule chaining is supported in forward and backward direction. The encapsulation feature of Marvel allows an easy integration of separate management tools. Policy enforcement is guaranteed, because every management activity is controlled by Marvel. Activity is initiated either by a human administrator or automatically by monitoring the status of the system. This allows the delegation of simple management tasks to the system. The potential for incorrect management decisions is reduced, because the rule interpreter checks every request for conformance with the given rules and the actually recorded status of the system.<<ETX>>