Service-Oriented Computing. ICSOC/ServiceWave 2009 Workshops

Identifying, gathering, and maintaining information on the current, planned, and target states of the architecture of an enterprise is one major challenge of enterprise architecture (EA) management. A multitude of approaches towards EA are proposed in literature greatly differing regarding the underlying perception of EA and the description of the function for performing EA. The aforementioned plurality of methods and models can be interpreted as an indicator for the low maturity of the research area or as an inevitable consequence of the diversity of the enterprises under consideration pointing to the enterprise-specificity of the topic. In this paper, we use a knowledge management perspective to analyze selected EA approaches from literature. Thereby, we elicit constituents, which should be considered in every EA function from the knowledge management cycle proposed by Probst. Based on the analysis results, we propose future research topics for the area of EA.

This paper presents a literature review on enterprise architecture principles. The results show that there are various gaps in the research literature: No accepted definition of enterprise architecture principles has emerged yet. A detailed conceptual framework is still lacking. Business principles, IT principles and enterprise architecture principles are often mixed up. Research into generic design principles is still in its infancy. Our review illustrates the necessity to conduct more research on enterprise architecture principles. We describe conceptual foundations and provide guidance for further research in this field.

Enterprise modeling has been an area of significant research in the information systems discipline throughout the last decade. Mainly developed by IT-practitioners, enterprise architectures (EA) became a promising and comprehensive approach to model either the current or desired state of enterprises. Existing approaches are, however, often criticized for paying too little attention to the business side of enterprises. In this paper, we interpret an enterprise as socio-technical system and analyze from a systems theory perspective which features are necessary for a comprehensive model. From there, we deduce if, why and how additional aspects of enterprises should be included into EA. Amongst others, it becomes obvious that especially human actors, as most flexible and agile elements of enterprises, are not adequately included in current architectures. We therefore present first ideas for integrating this important aspect into EA, the corresponding implications of such an inclusion, as well as several areas of further research.

Aside of day-to-day business in some organizations Enterprise Architecture (EA) seems to be successful while it is not in others that also have notations, models, methods, and even dedicated EA tools. In order to understand these differences we have analyzed the development of EA in six companies over the last eight years. Our analyses showed, that apart from formal structure and processes (i) training and education of architects and non-architects, (ii) improving architects’ communication skills, (iii) intensifying EA representation in projects, and (iv) tool support (not replacements with tools), significantly contribute to long term EA success.

The field of enterprise architecture is still very much in development. Many architecture teams are looking to improve their effectiveness. One of the instruments to do so is the Dynamic Architecture Maturity Matrix. In the past the DyAMM has been applied to many architecture practices to assess their architecture maturity level. In this paper we present an analysis of these assessments. This provides us with an overview of common strengths and weaknesses in existing architecture practices. In addition, we use the set of assessments to analyze the DyAMM instrument for four types of anomalies.

Rigorous modelling techniques and specialised analysis methods support enterprise architects when embarking on enterprise architecture management (EAM). Yet, while customised modelling solutions provide scalability, adaptability and flexibility they are often in conflict with generic or reusable visualisations. We present an approach to augment customised modelling with the techniques of model transformations and higher-order transformations to provide flexible and adaptable visualisations with a minimum of requirements for the underlying enterprise models. We detail our approach with a proof-of-concept implementation and show how a decoupling can ease EAM approaches and provide appropriate tooling in practice.

Service-oriented Architectures (SOA) are a powerful paradigm to address integration challenges for information technology systems in enterprises. The service-based integration of legacy systems and business partner systems makes it necessary to introduce and adapt suitable SOA security measures in order to secure the enterprise both within and for cross-organizational collaboration. While there is an active research community for SOA security, standard literature on the topic has not yet identified the influence of the SOA paradigm on security aspects in a structured manner, especially in an enterprise context. In our paper, we work towards this goal by identifying the main elements of cross-organizational SOA in the form of a conceptual model and by discussing these elements regarding their impact on security issues. Based on this, research challenges for SOA security are defined and structured.

We describe a service-oriented framework that supports how distributed enterprises can collaborate on doing work. Our model separates the concerns of

doing

from

managing

work. Work is modeled as a

capability

and can be provided as a

service

by some organization. A desired business outcome can then be described by its required capabilities. The framework enables dynamic composition of capabilities into

just-in-time service plans

that can be executed collaboratively by distributed organizations. A Hub is used to

manage

and coordinate the overall work. It comprises stakeholders from the collaborating organizations. The Hub’s infrastructure enables them to see the big picture, detect issues early, decide on the best response, and quickly enact their decision. Executing service plans can then be modified in real-time, providing the enterprise with agility and flexibility.

Business workflow assembles together a collection of tasks or activities in order to accomplish a business objective. Management of business workflows is facing many significant challenges, including in particular design, making changes, interoperations, etc. A key step in addressing these challenges is to develop techniques for mapping logical workflow specifications into executable workflow systems. In this paper we introduce a new artifact-centric workflow model called Artifact Conceptual Flow (ArtiFlow) and show that automated translation from ArtiFlow to BPEL is achievable. We also discuss technical issues in the translation.

Crowdsourcing has emerged as the new on-line distributed production model in which people collaborate and may be awarded to complete a task. While many existing services enable enterprises to employ the wisdom of crowd, there is no existing practice defined for integration of crowdsourcing with the business processes. We propose PeopleCloud, as the (1) mechanism to enable access to scalable workforce on-line, connecting it to the enterprise and (2) an interface to services required for crowdsourcing tasks. We define requirements for PeopleCloud, based on our experiences in employing wisdom of crowd to source business and IT information within the enterprise.

This paper explores the gap between

actual

work practices and their articulation. Our goal is to bring this gap to the forefront as an important consideration for operational process modeling. Business process models presuppose accurate disclosure of employee work practices. However, the presence of a gap between personal practices and their public disclosure is a challenge for accurately representing the true nature of business operations. We describe a field study of the working practices of a municipal organization where we identified this gap. We then offer several underlying motivations that contribute to the existence of this disparity. These findings hold important implications for global enterprises, and for process modeling efforts in general.

In the vision of the Internet of Services (IoS) services are offered and sold as tradable goods on an open marketplace. Services are usually consumed as part of service compositions defining complex business processes. In a service composition the execution of one service depends on other services. Thus, changes or problems during the provisioning of services may affect other services. While information about dependencies is necessary to handle problems and changes in service compositions, this information is usually only implicitly available in the process description and SLAs. In this paper, we propose an approach where the dependencies between services in a composition are analysed at design time and captured in a dependency model. This information is used to validate the negotiated SLAs to ensure that proper collaboration between the services is possible. At runtime this model can then be applied for determining the effects of events such as service failure (SLA is violated) or SLA renegotiation on other services. Our major contributions are a classification of service dependencies in business processes and an algorithm for semi-automatic dependency model creation based on a process description and the related SLAs. We have evaluated our approach based on a logistics scenario.

Logistics service providers are forced to optimize their operations due to increasing market pressure. Outsourcing and network optimization are measures to improve their market position. Although the underlying operational research problems in logistics are well documented and the business tendency towards outsourcing already manifests itself in the growth of many local multi vendor logistics providers, the connections between both parts into an innovative and integrated logistics concept is not yet established. Our OPEN Service-Oriented Computing for LOGistics (OPEN SOC LOG) approach proposes a system which integrates state-of-the-art optimization tools with a service-oriented computing concept in order to provide a spectrum of standardized and combinable services for logistics companies ranging from tour and network optimization to contractual and accounting functionalities.

The diffusion rate of Radio Frequency Identification (RFID) technology in supply chains is lower than expected. The main reason is the doubtful Return On Investment (ROI) mainly due to high tag prices. In this contribution, we leverage a prototypical RFID implementation in the fashion industry, extend this prototype by a discrete event simulation, and discuss the impact of an Electronic Product Code (EPC)-enabled supply chain concerning higher visibility. Thereby, we illustrate the benefit of the EPC network for Supply Chain Event Management (SCEM). Future researchers are provided with the simulation data which is available online and can be investigated.

Service level agreements (SLAs) establish the terms in which a logistics service may be provided or consumed. During the last years we have been studying techniques to perform an automated analysis of expressive and realistic SLAs, which makes the agreement creation process easier for involved parties. Firstly, we extended WS-Agreement specification to allow to apply any type of validity periods to SLA terms. Later, we dealt with the automated analysis of SLAs by proposing the explaining of SLAs inconsistencies and non-compliance scenarios. In this paper we show how these contributions are necessary to enable a logistic scenario of package tracking by providing examples for each proposal. We also include a final discussion on the convenience of performing a merge of all contributions to enable a better application of SLAs to logistic scenarios.

Moving towards a global market of services requires flexible infrastructures that will deal with the inevitable semantic heterogeneity that occurs during the negotiation that precedes the trading of a service. In order to reach an agreement, the negotiating parties need to understand the concepts describing the Quality of Service (QoS) terms which are part of the Service Level Agreement (SLA). The use of semantic annotations can increase the level of flexibility and automation, allowing the two parties to use their own terminology as long as it is related to the commonly understood conceptual model. This paper discusses how SLA negotiation will benefit from the use of a lightweight backwards compatible semantic annotation mechanism.

SLAs are contractually binding agreements between service providers and consumers, mandating concrete numerical target values which the service needs to achieve. For service providers, it is essential to prevent SLA violations as much as possible to enhance customer satisfaction and avoid penalty payments. Therefore, it is desirable for providers to predict possible violations before they happen, while it is still possible to set counteractive measures. We propose an approach for predicting SLA violations at runtime, which uses measured and estimated facts (instance data of the composition or QoS of used services) as input for a prediction model. The prediction model is based on machine learning regression techniques, and trained using historical process instances. We present the basics of our approach, and briefly validate our ideas based on an illustrative example.

Service-Oriented Architectures (SOA) represent an architectural shift for building business applications based on loosely-coupled services. In a multi-layered SOA environment the exact conditions under which services are to be delivered can be formally specified by Service Level Agreements (SLAs). However, typical SLAs are just specified at the customer-level and do not allow service providers to manage their IT stack accordingly as they have no insight on how customer-level SLAs translate to metrics or parameters at the various layers of the IT stack. In this paper we present a technical architecture for a multi-level SLA management framework. We discuss the fundamental components and interfaces in this architecture and explain the developed integrated framework. Furthermore, we show results from a qualitative evaluation of the framework in the context of an open reference case.

Cloud computing is receiving increasingly attention as it provides infinite resource capacity and “pay-as-you-go” resource usage pattern to hosted applications. To maintain its SLA targets, resource provisioning of service-oriented applications in the cloud requires reliable performance from the cloud resources. In this paper, we study performance behavior of small instances in Amazon EC2. We demonstrate that the performance of virtual instances is relatively stable over time with fluctuations of mean response time within at most 8% of the long-term average. Moreover, we also show that different supposedly identical instances often have very different performance, up to a ratio 4 from each other. We consider this as an important issue that must be addressed, but also as an opportunity as it allows one to assign each instance with a task that matches its own performance profile.

Assessing whether a company’s business practices conform to laws and regulations and follow standards, i.e., compliance governance, is a complex and costly task. Few software tools aiding compliance governance exist; however, they typically do not address the needs of who is in charge of assessing and controlling compliance, that is, compliance experts and auditors. We advocate the use of compliance governance dashboards, whose design and implementation is however challenging for these reasons: (i) it is fundamental to identify the right level of abstraction for the information to be shown; (ii) it is not trivial to visualize distinct analysis perspectives; and (iii) it is difficult to manage the large amount of involved concepts, instruments, and data. This paper shows how to address these issues, which concepts and models underlie the problem, and, how IT can effectively support compliance analysis in SOAs.

Service-oriented computing provides an evolving paradigm for flexible and scalable applications of open systems. Web services and their automatic composition are in the mainstream of the evolution of new value-added services. Functional and non-functional aspects are considered together for automatic service composition (ASC). After locating suitable functionality for the required composition, non-functionalities are considered to select the final set of services. Non-functional properties (NFPs) obtained from users or identified during planning or discovery usually have abstract concepts that cannot be identified at the selection stage. In this paper, we propose a transformation technique for automatic composition that identifies binding information in the selection stage from intermediate abstract NFPs. The classification of abstraction level in NFPs, a model to define abstract and concrete NFPs, and an algorithm for transformation from intermediate to concrete level are presented. The identification of the binding information is based on domain ontologies for services. Evaluation in our algorithm according to characteristics of NFPs is shown. Our work will contribute to modeling and identification of NFPs for ASC.

In the context of service discovery, matchmakers check the compliance of service-level objectives from providers and consumers. The problem of bounded uncertainty arises if some property is non-fixable. In this case, the provider is not able to control the value it takes at runtime, so the eventual consumer must not have the choice to select a value and fix it, but only knowing the guaranteed range of values it may take. To the best of our knowledge, there does not exist any approach which deals with this scenario. Most matchmakers work as if all properties were fixable, and a few have assumed the contrary. In either case, the accuracy of their results is likely to be in question since there may be involved both fixable and non-fixable properties at the same time, and there may also exist dependencies between them. In order to improve the accuracy, we present a holistic approach to matchmaking under bounded uncertainty and propose constraint programming as our choice to deal with it, so that matchmaking is transformed into a quantified constraint satisfaction problem.

Research into computing resource markets has mainly considered the allocative fairness of market mechanisms. It has not been discussed how a large variety of resource types influences the market liquidity. Markets containing large numbers of buyers and sellers for heterogeneous resources suffer from a low likelihood of matching offers and requests. Traders therefore have the high risk of not being able to trade resources. We suggest a solution that derives SLA templates from a large number of heterogeneous SLAs in the market and, by using these templates instead of the original SLAs, facilitates SLA mapping. The usefulness of this approach is demonstrated through simulation results and a comparison with an alternative approach, in which SLAs are predefined.

A Service Level Agreement (SLA) is the electronic equivalent of a real-life contract, which describes expectations from a service and governs its consumption. Ideally, a SLA provides certainty as regards customer experience and Quality of Service (QoS) received. For self-contained, isolated services this type of certainty is relatively straightforward to achieve. However, for services that are composed by others, or that rely on others to execute, such functional dependencies imply similar non-functional ones. Therefore, SLAs offered by a service to its customers are in turn depending on other SLAs, which the same service establishes in its role as a customer of the services it relies upon. In this paper we explore this dependency between different SLAs, and formalize the problem of converting an agreement for a composed service into individual agreements for the services from which it is composed.

In the last years we see a clear trend in the Computer Science area to a move towards Service-Oriented Architectures (SOAs). Research in the service domain encompasses its whole life-cycle, including topics as creation, discovery, selection, ranking and composition. This paper focuses on the ranking of discovered Web Services, proposing a novel approach based on non-functional properties of services: information that is available about services by analyzing their description that is available on the Web, their hyperlink relations, monitoring information, etc. The approach is making use of semantic technologies, aggregating the various real-world service aspects as described above in a unified model and providing different rank values based on those aspects.

This paper presents a platform that aims at monitoring and analyzing large service-oriented applications executing on a very large scale. This is part of a vision of web-scale service utilization and management that is proposed by the SOA4All EU project. The paper shows how the platform obtains data from distributed runtimes and how it presents monitoring information at different levels of abstraction. They range from low-level infrastructure-related event details to high-level service and process analysis. Each level uses appropriate visualization techniques and widgets in order to convey the relevant information to the users in an efficient manner. The platform is under development and an advanced prototype is already available and described in the paper.

Inspired by the biological perspective of service ecosystems, we propose to define the fitness of services in service networks. In our work, we show how to calculate the service fitness from the provider perspective using locally available information as a reflection of the position of the service in the service network. For that purpose we define a fitness corridor with upper and lower bounds that confine the service fitness area. After establishing a fitness corridor, we show how to calibrate the fitness calculation parameters to better reflect the service market and how to use the calculated fitness trends for making decisions about the provisioning of a service.

Process mining is an emerging analysis technique, which extracts process knowledge from data and provides various benefits to organizations. In Service Oriented Computing environment, different services collaborate with others to carry out the operations and therefore overall picture of operations and execution is not clear. Process mining extracts the information from log files of systems, as recorded during executions, and depicts the reality. In order to apply process mining, extraction of process trace data from log files is a pre-requisite step. A case study demonstrates the practical applicability of our proposed framework for extraction of the process trace data from application systems and integration portals.

The concept of self-managing of autonomic networks is a paradigm shift from today’s management models, aiming at enabling networked nodes to self manage their behaviour within the constrains of the operator’s policies and objectives. In this article, we present our approach for self-coordinating monitoring functions within such an autonomic network. This approach complies with the principles of a recently introduced

Reference Model

for autonomic network engineering/self-management within node and network architectures dubbed: the

Generic Autonomic Network Architecture (GANA)

, which aims to identify autonomic behaviours realised via hierarchical control loops among self-managing elements. The components of the proposed monitoring framework, the interactions among the identified elements and a complete use case scenario are described in detail.

Several techniques have been defined for the monitoring and adaptation of applications. However, such techniques usually work in isolation and cannot be easily integrated to tackle complex monitoring and adaptation scenarios. Furthermore, applications may have special requirements which make it difficult to reuse such off-the-shelf approaches. In particular, these requirements may cross several application layers such as – the organisation of stakeholder roles, coordination of planned activities, and integration with third-party services.

In this paper we outline a lightweight, loosely-coupled and extensible monitoring and adaptation framework that allows application developers to integrate monitoring and adaptation techniques as units that can be linked to solve complex requirements and achieve cross-layer adaptation. In order to cater for application-tailored adaptation units, we propose a pattern-based technique for the development and integration of adaptation units.

The heterogeneity and dynamicity of services, their underlying infrastructures make the problem of adaptation and monitoring an emerging issue for service-based applications (SBA). While various approaches aim to address these problems, most of them focus on a particular element of the SBA architecture. Indeed, those approaches are fragmented and isolated; they do not consider the effect of adaptations on the whole stack of the functional layers of SBA. In this paper we study the problem of cross-layer SBA monitoring and adaptation on a series of case studies and define the requirements for the integrated approaches that provide coherent solutions to monitor and adapt the whole application. Finally we propose the mechanisms and principles that are necessary for addressing the requirements and enabling an integrated cross-layer framework.

The emergence of self-managing networks can be seen as an enabler for increased dependability, reliability and robustness of the network layer. All these features are significant for the services and applications relying on the network infrastructure. This paper explores the links between traditional Fault-Management functions belonging to the management plane and the fundamental network functions for Resilience and Survivability embedded inside the protocol modules of a node/device. This results in an architectural framework that allows nodes/devices to implement the converging aspects of Fault-Management (now becoming autonomic), Resilience and Survivability in a self-managing network. The components and adaptation mechanisms of the proposed framework will make the network layer more robust and application/service aware. Thus, the dependability, reliability, and adaptability of the upper layer services and applications are expected to increase.

The need to change service-based systems during their execution time has been recognized as an important challenge in service oriented computing. There are several situations that may trigger changes in service-based systems such as unavailability or malfunctioning of services; changes in the functional, quality, or contextual characteristics of the services; changes in the context of the service-based system environment; emergence of new services; or changes in the requirements of the system. However, in order to support dynamic changes in service-based systems, it is necessary to have

replacement policies

describing

what

needs to be changed, and

how

and

when

the changes should be executed. In this paper, we describe replacement policies to support dynamic changes in service-based systems. These replacement policies are used in our service discovery framework that supports proactive identification of services in parallel to the execution of the system. A prototype tool has been implemented in order to illustrate and evaluate the framework. The results of some initial evaluation are also described in the paper.

Recent workflow languages are designed to serve the needs of business processes running in an unambiguous world based on unambiguous data. In contrast to business processes, processes running in a real world environment have to deal with data uncertainty and instability of the execution environment. Building a workflow language for real world flows based on a workflow language for business processes therefore may need additional modeling elements to be able to deal with this uncertainty and instability. Based on a real world process scenario we analyse and derive requirements for workflow language extensions for real world processes. The contributions provided by this paper are at first to investigate, how a workflow language can be extended properly followed up by the definition of workflow language extensions for real world processes, whereas the extensions are motivated by the real world process scenario. In this paper we use the Business Process Execution Language (BPEL) as extension foundation.

Business processes must become agile, respond to changes in the business environment in a timely manner and quickly adapt themselves to new conditions. Event-Driven Business Process Management (ED-BPM) is an enhancement of Business Process Management (BPM) by concepts of Service Oriented Architecture (SOA) and Complex Event Processing (CEP). The most important enhancement is the integration of services accessible via the Internet that fire events into global event clouds. The events can be processed by event processing platforms for aggregating the information into higher value complex business events. These events can be modeled in a business process execution language within a process driven Business Process Management System (BPMS) to trigger changes in control flow of a process or start other services. A reference model and a reference architecture for ED-BPM are presented, based on the NEXOF Reference Architecture. A taxonomy for classifying changes to process flow is proposed. Enhancements have to be applied to the existing standards in the BPM field, including both the design-time and the runtime. A scenario from the banking domain illustrates the main concepts and principles.

Dynamically changing economic environments require distributed Service-Based Applications (SBAs) to be highly flexible and reactive, so that the utilization of monitoring and adaptation functionalities becomes imperative. While approaches for monitoring functional and non-functional properties from the operational environment have gained a certain degree of maturity, there is still a lack of reflecting business-related aspects. This paper introduces the vision of a generic monitoring and adaptation framework focusing on the interactions between different abstraction layers of distributed SBAs. Starting from the business model perspective, strategic decisions are specified by the business model design in order to constitute the scope for possible operational adaptations at the business process, service and resource layers. Additionally, the monitoring of technical and business-related aspects affects not only the operational layers, but also the business model layer in the long-term.

When service-based applications implement business processes, it is important to monitor their performance in terms of Key Performance Indicators (KPIs). If monitoring results show that the KPIs do not reach target values, the influential factors have to be analyzed and corresponding adaptation actions have to be taken. In this paper we present a novel adaptation approach for service-based applications (SBAs) based on a process quality factor analysis. This approach uses decision trees for showing the dependencies of KPIs on process quality factors from different functional levels of an SBA. We extend the monitoring and analysis approach and show how the analysis results may be used to come up with an adaptation strategy leading to an SBA that satisfies KPI values.

This paper aims to investigate the most important aspects, features and requirements around the delivery of Multimedia services in cross-layer architectures that can be exploited for the development of autonomic service management middleware on the top of autonomic networking environments. Fundamental autonomic features like self-management, self-healing and self-adaptation are closely (re) considered and analyzed through the prism of network agnostic media adaptation and other application-layer management mechanisms with the aim to indentify the expected impact of autonomics in end user service deployment experience. The work describes on a high level the specific features and requirements of a proposed autonomic service management framework for the support of steaming media applications in fixed and mobile autonomic accessed networking environments. The work is part of the EFIPSANS project one of the largest research project in IPv6 enabled autonomic networks and

Extensions to IPv6 (IPv6++)

towards the Self-Managing Future Internet.

Several activities in service oriented computing can benefit from knowing ahead of time future properties of a given service composition. In this paper we focus on how statically inferred computational cost functions on input data, which represent safe upper and lower bounds, can be used to predict some QoS-related values at runtime. In our approach, BPEL processes are translated into an intermediate language which is in turn converted into a logic program. Cost and resource analysis tools are applied to infer functions which, depending on the contents of some initial incoming message, return safe upper and lower bounds of some resource usage measure. Actual and predicted time characteristics are used to perform predictive monitoring. A validation is performed through simulation.

The establishment of service orientation in industry determines the need for efficient engineering technologies that properly support the whole life cycle of service provision and consumption. One challenge is adequate support for service consumers for employing complex services in their individual application context, which becomes particularly important for large-scale enterprise technologies where generic services are designed for reuse in several business scenarios. This paper presents an approach for service customization by model-driven variability management. The variable aspects of the services are explicitly described on the basis of a metamodel. Upon this, service consumers can easily create personalized service variants that properly suit their specific context while the consistency for service invocation is maintained.

Quality attributes of software products like maintainability and reliability have been widely studied in the Software Engineering literature. Their understanding has proven instrumental for developing best practices and tooling support that ultimately result in higher-quality software.

In this paper we investigate external quality attributes (i.e. aspects of quality visible to the end user) of service choreographies. Service choreographies are service compositions that specify completely distributed, message-based interactions among services. Our work is a first step towards the definition of a quality model for service choreographies.

Migration of legacy assets to SOA embodies a key challenge of service engineering, the rehabilitation of pre-existing enterprise assets into a service based system. As there is still little conceptual characterization of what the legacy to SOA migration process entails it is difficult to understand, compare and assess different approaches. This paper therefore proposes a conceptual framework embracing a holistic illustration of such a migration process. We describe what such migration process entails and what distinct conceptual elements systematically define the process. Based on the constituting conceptual elements, the framework which is considered as a basis for understanding and assessment of different approaches is proposed. Finaly, the role of our migration framework in positioning and assessing the existing methods, is discussed.

The importance and benefits of Business Process Management (BPM) for organizations are nowadays broadly recognized, as not only the business area but also the information technology one are embracing and adopting the paradigm. The implementation of business processes as services helps in reducing the gap between these two areas, easing the communication and understanding of business needs. Although there is a general agreement on the benefits of the joint application of these two paradigms, some issues still need to be addressed; being a key one the automatic generation of services from business process models. In this article, we present MINERVA framework which applies Model Driven Development (MDD) and Service Oriented Computing (SOC) paradigms to business processes for the continuous business process improvement in organizations, supporting the different stages defined in the business process life cycle from modeling to evaluation of its execution.

Service-based applications are considered a promising technology since they are able to offer complex and flexible functionalities in widely distributed environments by composing different types of services. These applications have to be adaptable to unforeseen changes in the functionality offered by component services and to their unavailability or decreasing performances. Furthermore, when applications are made available to a high number of potential users, they should also be able to dynamically adapt to the current context of use as well as to specific requirements and needs of the specific users. In order to address these issues, mechanisms that enable adaptation should be introduced in the life-cycle of applications, both in the design and in the runtime phases. In this paper we propose an extension of a basic iterative service-based applications life-cycle with elements able to deal with the adaptation-specific needs. We focus, in particular, on the design phase and suggest a number of design principles and guidelines that are suitable to enable adaptation. We discuss about the effectiveness of the proposed methodology by means of real-world scenarios over various types of service-based applications.

The decentralized execution of business process instances is a promising approach for enabling flexible reactions to contextual changes at runtime. Most current approaches address such process distribution by

physical fragmentation

of processes and by dynamic assignment of resulting static process parts to different business partners.

In order to enable a more dynamic segmentation of such responsibilities at runtime, this paper proposes to use

process runtime migration

as a means of

logical process fragmentation

. Accordingly, the paper presents a general migration metadata model and a corresponding basic privacy and security mechanism for enhancing existing process models with the ability for runtime migration while respecting the intensions and privacy requirements of both process modelers and initiators. The approach is conceptually evaluated by applying it to WS-BPEL processes and comparing the results to the general concept of process fragmentation.

HTML forms are the predominant interface between users and web applications. Many of these applications display a sequence of multiple forms on separate pages, for instance to book a flight or order a DVD. We introduce a method to wrap these multi-stepped forms and offer their individual functionality as a single consolidated Web Service. This Web Service in turn maps input data to the individual forms in the correct order. Such consolidation better enables operation of the forms by applications and provides a simpler interface for human users.

To this end we analyze the HTML code and sample user interaction of each page and infer the internal model of the application. A particular challenge is to map semantically same fields across multiple forms and choose meaningful labels for them. Web Service output is parsed from the resulting HTML page. Experiments on different multi-stepped web forms show the feasibility and usefulness of our approach.

The theme of service-oriented computing is largely centered on reusing already existing services. Service providers model common features among potential applications, realize them as reusable services, and publish in service registries. Service consumers discover appropriate services and subscribe them. In developing application with reusable services, there exists a key technical problem, called mismatch problem which is a gap between the required feature and the feature of a candidate service. The adaptability of available services is a key factor in determining the reusability of the published services by resolving mismatches. Hence, we claim that the design of adapters should be an essential activity for developing service-oriented applications. In this paper, we identify recurring mismatch types in discovering services. And, we present four adapter patterns handling the mismatch problems. By using the adapter patterns, service providers could develop highly reusable services, and service consumers will be able to reuse more services available.

The huge demand for ad-hoc and situational enterprise-class applications led to a new kind of Web-based applications, known as enterprise mashups. End users from the business units with no programming skills are empowered to combine and reuse existing company internal and external resources within minutes to new value added applications. In order to handle the growing number of mashable components, we propose a context-aware concept for enterprise mashups that supports users to find relevant components according to their current situation and to compose them automatically. The designed context model which is structured in the three domains agent, computing and environment is implemented in the SAP Research RoofTop Marketplace prototype to demonstrate its applicability and business benefits.

The emerge of web services in Service-Oriented Architectures (SOA) within companies or at the global internet offers new ways for the creation of web applications. Even though the composition of services via business processes are covered by existing tools and solutions, concepts for a lightweight service consumption are still in a preliminary phase. The complexity of state-of-the-art SOA technology prevents users with limited IT skills getting easy access to web services and their offered functionalities. This paper presents a user-centric design approach to model and create simple service-based applications in a graphical way without being necessary to write any code.

Network-based software application services are receiving a lot of attention in recent years, as observed in developments as

Internet of Services

,

Software as a Service

and

Cloud Computing

. A service-oriented computing ecosystem is being created where the end-user is having an increasingly more active role in the service creation process. However, supporting end-users in the creation of a service, at runtime, is a difficult undertaking. Users are heterogeneous, have different requirements, preferences and knowledge. Furthermore, and since we cannot assume that all users are technical experts, we conclude that highly abstract mechanisms should be available to support the service creation process. To tackle these issues and provide end-users with personalised service delivery, we claim that runtime automated service composition mechanisms are required. In this paper we present the DynamiCoS framework, which aims at supporting the different phases required to provide users with automatic service discovery, selection and composition process. In this paper we also present the developed prototype and its evaluation.

This work extends and enhances existing semantic service models by involving users and by including service metadata related to the user’s view of the service and their behaviour. We borrow ideas and extend the models and practices for the annotation of Web content and information resources that has recently become popular in widely-used social platforms. Users are encouraged to describe in their own terms the services they use. Our approach strengthens user participation in the Web and more generally in the service industry by providing service metadata, which are later used as a form of lightweight user-side semantic annotation of services. This annotation is provided explicitly by the users and/or implicitly by identifying patterns in the users’ behaviour. This type of service annotation acts supplementary to the service descriptions provided by the service providers and is linked to the actual use of the services. Finally, we harvest the collected metadata and use it for facilitating discovery and clustering of services, as well as to enable service recommendations and matchmaking with users’ profiles.

In this paper, we investigate web users’ mental models of services, the underlying risks and benefits of service composition, and the problems anticipated while combining web services into complete interactive applications. The study comprised three focus groups integrating group discussions and questionnaires, with a total of 35 participants, the majority without specialist programming skills. The results of the focus groups revealed a high degree of optimism towards service composition and consumption. However, several concerns, primarily related to personal privacy, trust, and technical difficulty, were highlighted during the focus groups. This paper discusses these concerns and proposes some ideas about how to address them.

Ad-hoc and situational applications for personal use will gain more and more traction in the work support for knowledge workers (KWers). Personal information is a key element in these applications. Composition environments for situational applications like, e.g., Yahoo Pipes, enable end-users to compose services into an application targeting their individual problems. However, we analyze that these composition environments lack access for a KWer’s personal information and require redundant development of services for common KWer activities. Addressing these issues, we present an infrastructure that manages the KWer’s personal information consistently and thus provides services that serve as basis for enabling end-user driven service composition for application for personal use. The infrastructure consists of two key components, a basic personal information management system to maintain a KWer’s personal information cloud in a unified and integrated form and domain-specific services that offer business logic for frequently occurring activities in applications for a KWer’s personal use.

The FAST gadget development environment allows users to graphically compose intelligent, i.e., semantically annotated gadgets from predefined building blocks and deploy them on various mashup platforms, thus enabling the interconnection of different systems and services. In an environment where different parties use different ontologies to describe such building blocks, ontology matching is crucial. This paper discusses first steps in our effort to integrate ontology matching in an end-user-oriented environment such as FAST. We evaluate a number of tools and approaches for solving different levels of complexity in ontology matching and define the direction of integrating ontology matching into FAST.