Web service composition has been extensively studied in recent years. Although a lot of new models and mechanisms have been proposed, many issues in service composition still remain unsolved. Among them, forensics examination is one of the major concerns. As opposed to traditional forensics implementations, applying forensics to Web service infrastructures introduces novel problems such as the need for neutrality, comprehensiveness, and reliability. Existing approaches fail to recognize that even optimized strategies for service selection and composition involve the exchange of large amounts of potentially sensitive data, causing potentially serious forensics leaks. Consequently, forensics is still among the key challenges that keep hampering service composition-based solutions.

Web service composition has been extensively studied in recent years. Although a lot of new models and mechanisms have been proposed, many issues in service composition still remain unsolved. Among them, privacy is one of the major concerns. Indeed, inheriting characteristics of Web services environments such as high dynamism and untrustworthiness often generate conflicting privacy specifications with respect to the data exchanged within a composition. Even existing technologies for managing and applying data privacy policies are unsuccessful when dealing with this kind of applications as they involve autonomous entities and continuously exchange huge amount of heterogeneous information. This made urgent to have in place effective technologies for data privacy management in service compositions. These technologies should (1) deal with the flexibility, scalability, and heterogeneity in the overall infrastructure in which data are exchanged; and (2) integrate privacy concerns into the development process of these compositions. In this context, this paper tackles the problem of modeling, managing and preserving privacy in Web service composition processes. More specifically, we propose a first step towards providing a privacy preserving Web service composition approach that enables to (i) model and specify privacy policies, preferences, and requirements both at the client and at the provider sides, (ii) enforce the privacy model and build privacy aware compositions, (iii) verify the compliance between users privacy requirements and providers privacy policies, (iv) rank the composite Web services with respect to the privacy level they offer, and (v) provide privacy aware recovery actions to deal with incompatibilities.

Classifying Web services into functionally similar groups is an efficient way to enhance services discovery, composition, and substitution processes. In order to ensure such efficiency, the classification process should rely on adequate semantic similarity measures. This paper presents a practical approach to measure the similarity of Web services. Both semantic and syntactic descriptions are integrated through specific techniques for computing similarity measures between services. Formal Concept Analysis (FCA) is used then to classify Web services into concept lattices in order to facilitate relevant services identification for composition and/or substitution purposes. The proposed similarity measure is evaluated and compared to some of the best-known existing ones. Results show a significant improvement of precision and recall of relevant services discovery for further composition and substitution tasks.

Intrusion Detection System is considered as a core tool in the collection of forensically relevant evidentiary data in real or near real time from the network. The emergence of High Speed Network (HSN) and Service oriented architecture/Web Services (SOA/WS) putted the IDS in face of a typical big data management problem. The log files that IDS generates are very enormous making very fastidious and both compute and memory intensive the forensics readiness process. Furthermore the high level rate of wrong alerts complicates the forensics expert alert analysis and it disproves its performance, efficiency and ability to select the best relevant evidences to attribute attacks to criminals. In this context, we propose Alert Miner (AM), an intrusion alert classifier, which classifies efficiently in near real-time the intrusion alerts in HSN for Web services. AM uses an outlier detection technique based on an adaptive deduced association rules set to classify the alerts automatically and without human assistance. AM reduces false positive alerts without losing high sensitivity (up to 95%) and accuracy up to (97%). Therefore AM facilitates the alert analysis process and allows the investigators to focus their analysis on the most critical alerts on near real-time scale and to postpone less critical alerts for an off-line log analysis.

Since current heterogeneous Intrusion Detection Systems (IDSs) have not been designed to work in a cooperative manner, sharing security information among them poses a serious challenge especially in large-scale High Speed Networks (HSN) environment. The integration become more difficult when we should reduce computing and memory costs incurred by the high speed IDSs communication. Fortunately Web Services technology represents a good choice for IDSs integration thanks to its characteristics such as platform transparency and loose coupling. In this context, this paper presents a lightweight RESTful Communication model for coordinating different high speed distributed IDSs. Experimental results show an important gain in terms of data exchanged size and transmission time.

Web services provide an instantiation of the loosely coupled Service Oriented Architecture (SOA) and facilitate the process of enterprise application integration. However, with the explosive growth of the number of Web services published over the Internet, identifying a high quality of composite services by taking into account both functional and non-functional requirements of end users has become a real challenge that needs to be addressed. We propose in this paper an approach that adresses this challenge by considering a two-phase composition process. The composition first proceeds to generate an abstract plan based on Web service types using Dynamic Description Logics (DDL). This abstract plan is then concretized into an executable plan by selecting the appropriate Web service instances based on non-functional requirements.

To exploit the true potential of Web services, it is critical to develop technologies and tools for composing new services from existing ones. Indeed, to reduce development time and integration efforts, this process of service composition requires an effective development environment to facilitate quick and simple composition of Web services, and remains a key challenge to realize the true potential of Web services. While numerous composition approaches have been developed, very little has been done towards providing an Integrated Development Environment to ease the process of composition. In this context, this paper introduces a new incremental approach to service composition engineering and considers the composition global life-cycle, i.e. specifying, composing, verifying, deploying, monitoring, and analyzing to achieve a full governance of the composition.

Due to the large number of sensor manufacturers and differing accompanying protocols, integrating diverse sensors into observation systems is not straightforward. A coherent infrastructure is needed to treat sensors in an interoperable, platform-independent and uniform way. The concept of the Sensor Web reflects such a kind of infrastructure for automatically discovering and accessing appropriate information from heterogeneous sensor devices over the Internet. In this context, the Open Geospatial Consortium (OGC) established the Sensor Web Enablement (SWE) initiative that specifies standard interfaces and encodings to remotely access, encode and exchange the sensed data. However, SWE standards have several gaps that limitate its capabilities to achieve the sensor Web desires. In this paper, we address the problems related to the data format and the architectural style followed by the implementation of the SWE services. Indeed, we propose the adoption of the lightweight Representational State Transfer (REST) web services concept and the usage of JavaScript Object Notation (JSON) format as an alternative to the verbose XML one for the exchanged messages.

While the rise of the Internet and the high speed networks made information easier to acquire, faster to exchange and more flexible to share, it also made the cybernetic attacks and crimes easier to perform, more accurate to hit the target victim and more flexible to conceal the crime evidences. Although people are in an unsafe digital environment, they often feel safe. Being aware of this fact and this fiction, the authors draw in this paper a security framework aiming to build real-time security solutions in the very narrow context of high speed networks. This framework is called (f|p) since it is inspired by the elefant self-defense behavior which yields p (22 security tasks for 7 security targets).

Different from process components, Web services are defined independently from any execution context. A key challenge of (Web) service compositions is how to ensure reliable execution. Due to their inherent autonomy and heterogeneity, it is difficult to reason about the behavior of service compositions especially in case of failures. Therefore, there is a growing interest for verification techniques which help to prevent service composition execution failures. In this paper, we propose an event-driven approach to validate the transactional behavior of service compositions. The transactional behavior verification is done either at design time to validate recovery mechanisms consistency, or after runtime to report execution deviations and repair design errors, and therefore, formally ensure service execution reliability. By using the Event Calculus formalism to specify and check the transactional behavior consistency of service composition, our approach provides a logical foundation to ensure service execution reliability.

To automate the analysis of service descriptions, [?] proposed a simple and expressive business protocol model (the specification of possible message exchange sequences) based on state machines, supporting rich timing constraints. Furthermore, developers of client applications need to be aware not only of functional aspects but also of non-functional aspects including privacy. In fact, the major concerns of a client are the disclosure of its personnel data conveyed during the message exchange. The aim of the paper is to study the ability of business protocol to handle the privacy and its time-related properties.

Notice of Plagiarism: This paper has been suppressed because it was found to plagiarize the following earlier works:

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

Due to the inherent autonomy and heterogeneity of Web services, ensuring composite services reliability remains a challenging problem. Extending the classical control flow with a transactional flow (encapsulating a set of recovery mechanisms) is widely accepted for ensuring composite services reliability. However, current approaches define recovery mechanisms in and ad-hoc way while they have to respect consistency rules regarding the control flow. In this paper, we propose a formal model based on event calculus for capturing both control and transactional flow of composite services. Following a pattern based modelling approach, we depict a set of rules characterising consistent transactional flow that can be defined w.r.t a given control flow. In addition, we propose two complementary approaches for enhancing composite services reliability.

Current Web services composition proposals, such as BPML, WSBPEL, WSCI, and OWLS, provide solutions for describing the control and data flows in Web service composition. However, such proposals remain at the descriptive level, without providing any kind of mechanisms or tool support for analysis and verification. Therefore, there is a growing interest for the verification techniques which enable designers to test and repair design errors even before actual running of the service, or allow designers to detect erroneous properties and formally verify whether the service process design does have certain desired properties. In this paper, we propose to verify Web services composition using an event driven approach. We assume Web services that are coordinated by a composition process expressed in WSBPEL and we use event calculus to specify the properties and requirements to be monitored.

Availability of a wide variety of Web services over the Internet offers opportunities of providing new value added services built by composing them out of existing ones. By integrating individual existing Web services the technology enables the provision of advanced and sophisticated services, such as allowing users to use different types of resources and services simultaneously in a simple procedure. However the management and maintenance of a large number of Web services is not easy and, in particular, needs appropriate authorization policies to be defined so as to realize reliable and secure Web Services. The required authorization policies can be quite complex, resulting in unintended conflicts, which could result in information leaks or prevent access to information needed. This paper proposes a logic based approach using for specifying authorization policies and detecting conflicts resulting from the combination of various kinds of authorization and constraint policies used in Web services environments. The method not only enables static detection of policy conflicts but also yields information that is helpful for correcting the policies. An automated induction-based theorem prover SPIKE is used as verification back-end.