Abstract: The Web service selection phase is usually driven only by functional requirements. Non functional requirements, such as quality of service, should be negotiated by the service consumer and the service provider during service invocation in order to produce a contract to manage service provisioning and to monitor the actual fulfilment of negotiated SLAs. In this paper, an automated approach to Web service QoS negotiation is proposed; the negotiation is performed by a negotiation broker to which both the consumer and the service provider can notify their preferences on QoS attributes and negotiation strategies by specifying the value of a relatively small set of parameters. When consumers are unable to specify such parameters or do not trust the service provisioning platform, negotiation can also be automated only on the provider side, allowing the direct interaction of the service consumer with the broker. An architecture to support the above mentioned functionalities is also described.

Abstract: In model driven development (MDD), specifying transformations between models at various levels of abstraction can be a complex task. Specifying transformations for pervasive system features that are tangled with other system features is particularly difficult because the elements to be transformed are distributed across a model. This paper presents an aspect oriented model driven framework (AOMDF) that facilitates separation of pervasive features and supports their transformation across different levels of abstraction. The framework is illustrated using an example in which a platform independent model of a banking application is transformed to a platform specific model.

Abstract: As enterprise services increasingly interconnect as networked services in a service-oriented architecture (SOA), service level management (SLM) is becoming a complex problem and can no longer be handled by traditional monitoring tools like Microsoft SMS. SLM is a process managing the quality of services demanded by clients and offered by providers. This paper presents two contributions to the research of SLM. First, instead of considering monitoring as an isolated service, it incorporates monitoring as an integral part of a comprehensive QoS management framework. This framework consists of QoS management concepts and services including service level contract management, admission control, resource management, monitoring, diagnostics, and adaptation. Using this framework, clients are able to negotiate quality of service contracts with providers and providers are able to optimize system resources to meet contract requirements. The second contribution is the incorporation of diagnostic service in the QoS management framework. Based on data feed from monitoring service, diagnostic service is able to detect any condition changes and to reason about the causes of any degradation conditions in the networked enterprise system. With condition detection and situation understanding, QoS management can then proactively activate adaptation mechanisms to maximize the system's ability to meet QoS contract requirements of concurrent clients. Our monitoring service uses both reporting approach and probing approach to acquire the information of the health status of elements of a networked system. The monitored data is then fed to our diagnostic service to reason about root causes of anomalies, using graphical models. Depending on the system health status and root causes, appropriate adaptations are triggered proactively to improve the system performance under the constraints of concurrent QoS contracts. We validate our SLM approach using QoS management services integrated in a publish/subscribe style of SOA. We then demonstrate via experiments some benefits of QoS monitoring, diagnostics, and adaptation services for responsiveness SLM.

Abstract: The use of open, Internet-based communications for business-to-business (B2B) interactions requires accountability for and acknowledgment of the actions of participants. Accountability and acknowledgment can be achieved by the systematic maintenance of an irrefutable audit trail to render the interaction non-repudiable. To safeguard the interests of each party, the mechanisms used to meet this requirement should ensure fairness. That is, misbehaviour should not disadvantage well-behaved parties. Despite the fact that Web services are increasingly used to enable B2B interactions, there is currently no systematic support to deliver such guarantees. This paper introduces a flexible framework to support fair non-repudiable B2B interactions based on a trusted delivery agent. A Web services implementation is presented. The role of the delivery agent can be adapted to different end user capabilities and to meet different application requirements.

Abstract: In this paper we propose an approach for the integration of functional models with non-functional models in the context of model-driven e-service development. Starting from the observation that current approaches to model-driven development have a strong focus on functionality, we argue the necessity of including non-functional aspects, as early as possible in the service design process, from the architectural (computational independent) level through all MDA layers. Furthermore, we distinguish between two modelling spaces (orthogonal to the MDA view), the design space and the analysis space, which could be integrated by means of model transformations. Thus, relating the analysis results to the original design models can be achieved by following a sequence of steps that entail horizontal model-to-model transformations from the design space to the analysis space, vertical model-to-model transformations (within and between the MDA layers) and proprietary analysis techniques that are used for the derivation of required (quantitative) properties. This provides a framework for incorporating nonfunctional analysis into methodological support for e-service development.

Abstract: Mobile health systems can extend the enterprise computing system of the healthcare provider by bringing services to the patient any time and anywhere. We propose a model-driven design and development methodology for the development of the m-health components in such extended enterprise computing systems. The methodology applies a model-driven design and development approach augmented with formal validation and verification to address quality and correctness and to support model transformation. Work on modelling applications from the healthcare domain is reported. One objective of this work is to explore and elaborate the proposed methodology. At the University of Twente we are developing m-health systems based on body area networks (BANs). One specialization of the generic BAN is the health BAN, which incorporates a set of devices and associated software components to provide some set of health-related services. A patient has a personalized instance of the health BAN customized to their current set of needs. A health professional interacts with their patients' BANs via a BAN professional system. The set of deployed BANs are supported by a server. We refer to this distributed system as the BAN System. The BAN system extends the enterprise computing system of the healthcare provider. Development of such systems requires a sound software engineering approach and this is what we explore with the new methodology. The methodology is illustrated with reference to modelling activities targeted at real implementations. In the context of the awareness project BAN implementations are tested in a number of clinical settings including epilepsy management and management of chronic pain.

Abstract: Data warehouse (DWH) information is accessed by business processes, and sometimes may also initiate changes of the control flow of business process instances. Today, there are no conceptual models available that make the relationship between the DWH and the business processes transparent. In this paper, we extend the event-driven process chain, a business process modeling language, with an additional perspective to make this relationship explicit in a conceptual model. The model is tested with example business processes.

Abstract: The ODP computational viewpoint describes the functionality of a system and its environment in terms of a configuration of objects interacting at interfaces, independently of their distribution. Up until UML version 2.0, both the lack of precision in the UML definition and the semantic gap between the ODP concepts and the UML constructs hindered its application for ODP computational viewpoint modeling. With the advent of UML 2.0 the situation may have changed, because its semantics have been more precisely defined and it now incorporates a whole new set of concepts more apt for modeling the structure and behavior of distributed systems. In this paper, we explore the benefits provided by the new extension mechanisms of UML and, more specifically, we present a UML profile for modeling the ODP computational viewpoint concepts. We also show a case study that illustrates how our proposal is applied to a multimedia distributed system.

Abstract: In a model-driven design process the interaction between application parts can be described at various levels of platform-independence. At the lowest level of platform-independence, interaction is realized by interaction mechanisms provided by specific middleware platforms. At higher levels of platform-independence, interaction must be described in such a way that it can be further refined and realized onto a number of different middleware platforms, each with its particular interaction mechanisms and implementation constraints. In this paper, we investigate concepts that support interaction design at various levels of middleware-platform-independence. Also, we propose design operations for interaction refinement. The application of these operations to source designs results in target designs that take into account implementation constraints imposed by platforms, while preserving characteristics prescribed in source designs.

Abstract: Assessing the level of information security in an enterprise is a serious challenge for many organizations. This paper considers the prioritization of the field of enterprise information security. The paper thus considers how we may know what parts of information security are important for a company to address and what parts are not. Two methods for prioritization are used. The results demonstrate to what extent different standards committees, guideline authors and expert groups differ in their opinions on what the important issues are in enterprise information security. The ISO/IEC 17799, the NIST SP 800-26, the ISF standards committees, the CMU/SEI OCTAVE framework authors and an expert panel at the Swedish Information Processing Society (DFS) are considered. The differences in prioritization have important consequences on enterprise information security assessments. The effects on the information security assessment results in a European energy company are presented in the paper.

Abstract: A large enterprise generates millions of purchase orders (PO) each year buying various types of goods and services. Each PO has a cost associated with it. This cost comprises multiple elements including the price of the good or service, the shipping and handling of the purchase, and the overhead in initiating, generating, tracking, and managing the PO. To reduce the cost of doing business, it is imperative to reduce the total cost of POs in enterprise e-procurement in an automated fashion. One way to reduce enterprise procurement cost is to aggregate demands so that the total cost of a bunch of POs is reduced by a better price, a lowered shipping and handling fee, and a reduced overhead. The cost of goods and services often depend on several factors including volume, timing, and other business objectives. This paper describes an intelligent aggregation approach for automatically aggregating demands to reduce procurement cost in enterprise e-procurement. Our aggregation approach for e-procurement consists of an information model for representing products (goods or services) and representing purchase orders for such products, a corporate agreement system, a negotiation engine, and a rule-based aggregation engine. The information model is based on an extension of the classic entity-relationship model. The extension enables association of rules and constraints with and among attributes. These rules and constraints must be satisfied during PO aggregation and thus ensure the aggregate PO to be consistent with original individual POs. A rule-based aggregation engine examines POs as they arrive and interact with other decision aids to determine whether aggregation of a particular bunch of POs makes any business sense. Aggregation can happen in two business scenarios, one for POs constrained by existing corporate agreements and another for POs to be refined by online negotiations. The aggregation engine interacts with a corporate agreement system to obtain supplier policies in the first scenario. For the second scenario, it interacts with the negotiation engine to obtain supplier's policies during iterations of the negotiation process. Relevant policies are those that define product pricing, shipping and handing, and post-sale sendees as well as warranties and returns. Examples are given to demonstrate how automated intelligent aggregation of purchases is performed and how it reduces cost in enterprise e-procurement.

Abstract: It is now recognized that nonfunctional properties are important to practical software development and maintenance. Many of these properties involve time and probabilities - for example, reliability and availability. In this paper, we present a framework for runtime verification of timed and probabilistic nonfunctional properties of component-based architectures, built using the meta-object facility and the Distributed Management Task Force's common information model (CIM) standard. We describe a Microsoft .NET-based implementation of our framework. We use a language for contracts based on probabilistic computational tree logic (PCTL). We provide a formal semantics for this language based on possible application execution traces. The semantics is parametrized with respect to the choice of application states and state changes to be monitored. This enables us to use the language to define a wide range of nonfunctional properties. We explain how our framework associates constraints with systems that expose management information through the CIM, via a novel extension of the CIM metamodel.

Abstract: OWL-S is an instance of the Web Ontology Language (OWL) that is used to describe and specify semantic Web services. While OWL-S provides a promising mechanism for specification, publication, discovery, integration, and access, the learning curve can be high. Current practices in Web services tend to focus on lightweight specification using automated tools that generate WSDL descriptions. One of the advantages of OWL-S is its flexibility in allowing the creation of many groundings or bindings for a single semantic Web service. In this paper, we propose an approach for generating groundings for a semantic Web service and demonstrate how the use of lightweight interactive tools facilitates creation of groundings for a semantic Web service.

Abstract: Nowadays, enterprise application integration (EAI) constitutes a real and growing need for most of enterprises, especially for large and dynamic enterprises of heterogeneous, autonomous and distributed information systems. Actually, the major problem of EAI is the heterogeneity problem, especially the semantic integration one. This latter is not correctly addressed by today's solutions, which focus mainly on technical and syntactical integration. Dealing with the semantic aspect, which certainly promotes EAI by providing it more consistency and robustness, needs some appropriate principles such as the knowledge or ontology urbanization. This latter constitutes the main focus of this paper. It aims to favour the semantic application integration, precisely by providing it more appropriate knowledge structuring that can help any enterprise to correctly capture, structure and master its semantics, which constitutes a big challenge for several enterprises that are in quest of more flexibility and manageability.

Abstract: As an intermediate step within a larger endeavor aiming at the definition of automatic transformations between two widespread technologies, namely EJB and .Net components, we propose and discuss a metamodel for the .Net platform that captures the appropriate modeling concepts required for the definition and automatic generation of .Net PSMs from (legacy) J2EE PSMs.

Abstract: Transactions are an important part of most enterprise computing systems. Sometimes they are supported by DBMS and sometimes by transaction monitors. In either case, they are part of the platform used by application developers. A platform independent model of enterprise computing must abstract away transactions and provide platform independent ways of describing them. This paper shows how "unit of work" can be used to support platform independent descriptions of enterprise computing systems that use transactions. Our paper is in the context of the OMG's model driven architecture so we provide a UML profile for describing unit of work. We have developed a tool, Mercator, that can translate platform independent models using the unit of work profile to platform dependent models using transactions. When added to our previous work on persistence, this provides a general way of handling transparent transaction management in MDA.

Abstract: This paper describes an approach towards workflow management based on the combination of learning and planning. Assuming that processes cannot be fully described at build-time, the approach makes use of learning techniques, namely inductive logic programming (ILP), in order to discover workflow activities as planning operators. These operators are subsequently fed to a partial-order planner in order to find the process model as a planning solution. The continuous interplay between learning, planning and execution aims at arriving at a feasible plan by successive refinement of the operators. The approach is illustrated in two simple scenarios. The paper concludes by relating the proposed approach with previous developments in this area.

Abstract: Content-based publish/subscribe offers a convenient abstraction for information producers and consumers, supporting a large-scale system design and evolution by integrating several distributed independent application systems. Unlike in the traditional address-based unicast or multicast, its core problem is how to match events by predicates on the content of events. In existing matching approaches, matching predicates are composed by the conjunction and disjunction of non-semantic constraints. But, in context of enterprise application integration, although they can match events by their contents, this traditional matching predicates are not expressive enough in manipulating the complex event matching, such as the "one-to-many" and "many-to-one" matching. Therefore, traditional matching approaches should be extended to solve the complex matching problems. After analyzing information matching patterns in enterprise application integration, we propose three matching models, extend this simple matching approach to the multi-semantic matching approach and further introduce the temporal constraint variable. The multi-semantic matching approach allows using different operations in accordance with different semantics; the temporal constraint variable supports processing several discrete events in temporal sequences. Then, we extend OBDD graphs into hierarchy coloured OBDD graphs and prove the equivalence of the transformation. Based on the extended OBDD graphs, the composite matching algorithm is presented and analysed. By experiments, we show the proposed algorithm is efficient.

Abstract: The development of many highly dynamic environments, like pervasive environments, modified the behavior of users and consequently, their expectations from systems and applications used in these environments. Thus, a user equipped with a laptop can connect to different places, and, each time, like to use his applications integrating the functionalities offered by the physically or logically close environment. In this article, we offer the architecture of a system of automatic negotiated integration of services. This integration introduces the elements of decision of the integration (negotiation, automatisation) and an interface Integrable making possible the application of different techniques of integration (parameterization, downloading/uploading - deployment, composition, weaving).

Abstract: This paper presents a formal system for reasoning about violations of obligations in contracts. The system is based on the formalism for the representation of contrary-to-duty obligations. These are the obligations that take place when other obligations are violated as typically applied to penalties in contracts. The paper shows how this formalism can be mapped onto the key policy concepts of a contract specification language. This language, called Business Contract Language (BCL) was previously developed to express contract conditions of relevance for run time contract monitoring. The aim of this mapping is to establish a formal underpinning for this key subset of BCL.

Abstract: We continue the study, started in [5], on the formal relationships between a domain specific contract language (BCL) and the logic of violation (FCL) proposed in [6,7] We discuss the use of logical methods for the representation and analysis of business contracts The proposed analysis is based on the notions of normal and canonical forms of contracts expressed in FCL Finally we present a mapping from FCL to BCL that can be used to provide an executable model of a formal representation of a contract

Abstract: This paper presents a service-oriented design approach that allows one to relate services modelled at different levels of granularity during a design process, such as business and application services. To relate these service models we claim that a 'concept gap' and an 'abstraction gap' need to be bridged. The concept gap represents the difference between the conceptual models used to construct service models by different stakeholders involved in the design process. The abstraction gap represents the difference in abstraction level at which service models are defined. Two techniques are presented that bridge these gaps. Both techniques are based on the Interaction System Design Language (ISDL). The paper illustrates the use of both techniques through an example.

Abstract: The Web services architecture came as answers to the search for interoperability among applications. There has been a growing interest in deploying on the Internet applications with high availability and reliability requirements. However, the technologies associated with this architecture still do not deliver adequate support to this requirement. The model proposed in this article is located in this context and provides a new layer of software that acts as a proxy between client requests and service delivery by providers. The main objective is to ensure client transparent fault tolerance by means of the active replication technique. This model supports the following faults: value, omission and stops. This paper describes the features and outcomes obtained through the implementation of this model.

Abstract: To form and automatically manage partnerships within a virtual organisation, it is necessary to have an electronic representation of the contract governing business relationships that can be used to mediate the rights and obligations that each interacting entity promises to honour. The paper describes a general method of representing business interactions using a widely used modelling language Promela and discusses how to represent permissions, obligations, prohibitions, actors (agents), time constraints, and message type checking; that is, all the basic parameters that compose most typical business contracts. Two levels of contract representations are described: implementation neutral, and implementation specific, that is a refinement of the former to include technical details such as acknowledgements and synchronization messages that form an important part of any implementation.

Abstract: The paper proposes a more formalized definition of UML 2.0 activity diagram semantics. A subset of activity diagram constructs relevant for business process modeling is considered. The semantics definition is based on the original token flow methodology, but a more constructive approach is used. The activity diagram virtual machine is defined by means of a metamodel, with operations defined by a mix of pseudocode and OCL pre- and postconditions. A formal procedure is described which builds the virtual machine for any activity diagram. The relatively complicated original token movement rules in control nodes and edges are combined into paths from an action to action. A new approach is the use of different (push and pull) engines, which move tokens along the paths. Pull engines are used for paths containing join nodes, where the movement of several tokens must be coordinated. The proposed virtual machine approach makes the activity semantics definition more transparent where the token movement can be easily traced. However, the main benefit of the approach is the possibility to use the defined virtual machine as a basis for UML activity diagram based workflow or simulation engine.

Abstract: The management of IT landscapes consisting of thousands of business applications, different middleware systems, and supporting various business processes is a challenge for modern IT management. The BMW Group has addressed this challenge by establishing an integrated IT management process which covers strategy, architecture, planning and controlling. The BMW Group integrates the following preexisting IT processes in a continuous management process: "architecture and standardization" defines blueprints in terms of architectural patterns; "landscape management" maintains an overall model of the (present and future) IT landscape; "portfolio management" coordinates, evaluates and prioritizes action items with IT impact; "synchronization management" manages ongoing (IT) projects, their dependencies and the cross functions; "strategy and objectives" generates action items, defines guidelines for the other processes and adjusts strategies based on feedback from the other processes. This paper describes the problems that arise if such an integrated, continuous management process is lacking.