Service Oriented Architecture Environment Research Articles

The Multiple Multidimensional Knapsack with Family-Split Penalties

The Multiple Multidimensional Knapsack Problem with Family-Split Penalties (MMdKFSP) is introduced as a new variant of both the more classical Multi-Knapsack and Multidimensional Knapsack Problems. It reckons with items categorized into families and where if an individual item is selected to maximize the profit, all the items of the same family must be selected as well. Items belonging to the same family can be assigned to different knapsacks; however, in this case, split penalties are incurred. This problem arises in resource management of distributed computing contexts and Service Oriented Architecture environments. An exact algorithm based on the exploitation of a specific combinatorial Benders’ cuts approach is proposed. Computational experiments on different sets of benchmark test problems show the effectiveness of the proposed algorithm. The comparison against a state-of-the-art commercial solver confirms the validity of the proposed approach considering also the scalability issue.

From CommonKADS to SOA Environment: An Adaptation Model

Common knowledge acquisition and documentation structuring (CommonKADS) methodology is used for building knowledge-based systems. Legacy systems built depending on CommonKADS suffer from weak points regarding reusability. The main objectives of this work are: (1) switching of CommonKADS methodology from just a design model to be an executable application, (2) facilitating the linkage and cooperation between CommonKADS services that are using different terminologies and (3) enhancing suitability and reusability of existing CommonKADS-based systems. An enhancement to the CommonKADS methodology in order to improve its applications reusability is introduced. This enhancement contains an adaptation of the original CommonKADS methodology and utilization of service-oriented architecture (SOA) as a promising software engineering technology. The proposed adaptation model includes two alternative processes: adjusting and converting. An adjusting process performs a transformation of the existing CommonKADS layers to be SOA-enabled so that it includes representing the data in a new standard form to be transformed into set of services. Converting process is concerned with changing CommonKADS-based legacy systems to SOA-enabled systems through using GenericSOA framework. An example application, a potato CommonKADS-based expert system, was used to evaluate the new proposed model through the analysis and automated restructuring of it to be SOA-enabled system.

Service oriented product lines - managed service level agreements for better quality of service

Service Oriented Architecture (SOA) is being used for developing service oriented applications as a set of business specific web services and gives more flexibility for the software development industry. However, systematic reusability for developing applications to fit customers' individual needs with high customization is significant to increase the productivity and reusability of such service oriented applications. Software Product Line (SPL) has the ability to prepare core sets of assets in an identifiable and reusable manner with manageable variable components. Thus, the combination of SOA and SPL has highlighted the term of Service Oriented Product Line (SOPL), which is used for increasing levels of flexibility and reusability. It helps to develop semantics of variability over identified service components. Likewise, Quality of Service (QoS) attributes play an important role in selection of web services in a SOA environment. Service Level Agreements (SLAs) provide the mechanism with a specification of the verifiable Quality attributes in web services. In this paper, we present our implementation approach of SOPL to manage Service Level Agreements (SLAs) in SOPL environments by monitoring Quality of Service (QoS) attributes in bundles of web service components. The design and development of service bundles for representing core sets of assets in SOPL are followed by the initial feature based analysis and identification of service components. The management of SLAs is handled by detecting the deviation between actual and acceptable predefined QoS metrics values in previously analysed web service components via Web Service Level Agreement (WSLA) language specified templates. The case study based evaluation results indicate the usefulness of research contribution.

Adaptive security architecture for protecting RESTful web services in enterprise computing environment

In this modern era of enterprise computing, the enterprise application integration (EAI) is a well-known industry-recognized architectural principle that is built based on loosely coupled application architecture, where service-oriented architecture (SOA) is the architectural pattern for the implementation of EAI, whose computational elements are called as “services.” Though SOA can be implemented in a wide range of technologies, the web services implementation of SOA becomes the current selective choice due to its simplicity that works on basic Internet protocols. Web service technology defines several supporting protocols and specifications such as SOAP and WSDL for communication with client and server for data interchange. A new architectural paradigm has emerged in SOA in recent years called REpresentational State Transfer (REST) that is also used to integrate loosely coupled service components, named RESTful web services, by system integration consortiums. This SOA implementation does not possess adequate security solutions within it, and its security is completely dependent on network/transport layer security that is obsolete owing to latest web technologies such as Web 2.0 and its upgraded version, Web 3.0. Vendor security products have major implementation constraints such as they need secured organizational environment and breach to SOA specifications, hence introducing new vulnerabilities. Herein, we examine the security vulnerabilities of RESTful web services in the view of popular OWASP rating methodologies and analyze the gaps in the existing security solutions. We hence propose an adaptive security solution for REST that uses public key infrastructure techniques to enhance the security architecture. The proposed security architecture is constructed as an adaptive way-forward Internet-of-Things (IoT) friendly security solution that is comprised of three cyclic parts: learn, predict and prevent. A novel security component named “intelligent security engine” is introduced which learns the possible occurrences of security threats on SOA using artificial neural networks learning algorithms, then it predicts the potential attacks on SOA based on obtained results by the developed theoretical security model, and the written algorithms as part of security solution prevent the SOA attacks. This paper is written to present one of such algorithms to prevent SOA attacks on RESTful web services along the discussion on the obtained results of the conducted proof-of-concept on the real-time SOA environment. A comparison of the proposed system with other competing solutions demonstrates its superiority.

Goal-driven adaptive monitoring of SOA systems

The advent of the Service Oriented Architecture (SOA) enabled implementation of IT systems of increasing complexity, rendering effective monitoring a nontrivial task. The inherent scale and dynamism of such systems does not allow for simultaneous monitoring of all system elements without introducing noticeable overhead. Therefore, an important challenge arises in the field of SOA monitoring. There is a need for a solution which enables on-demand adjustment of the monitoring process in accordance with the demands of system administrators and the changing conditions of the execution environment. The paper addresses the identified need by proposing the concept of goal-driven adaptive monitoring, capable of performing dynamic management of the monitoring process. The proposed concept is used for designing the Dynamic Adaptive Monitoring Framework, referred to as DAMON, which can be installed in an existing SOA environment to provide it with adaptive monitoring features. For the purpose of evaluation, a prototype of the DAMON framework was implemented on the basis of the OSGi technology. The evaluation, presented in the paper, not only verified the functional aspects of DAMON, but it also proved that the framework can decrease the monitoring overhead in large-scale dynamic systems.

Privacy Protection for Role-Based Access Control in Service Oriented Architecture

Service Oriented Architecture (SOA) changes the way of conducting business by opening their services/information to the larger business world over the networks. However, properties of and interoperable of SOA make privacy security a sensitive issue since this architecture combines unknown individuals and individuals systems together. In SOA, service providers limit the permission of access to specific authorized individuals only, so they have to verify these individuals' identity information to decide if permission should be granted or not. On the other hand, access requestors are not willing to disclose their privacy in an open system to unknown parties. In this thesis, we present cryptography-based protocols to solve this issue of conflict. Our protocols are proposed for Role-Based Access Control (RBAC), which is a most popular access control methodology, in SOA environment. In addition, our protocols are compatible with current SOA standards and technologies such as XACML and SOAP.

A Knowledge-Based System Approach for Extracting Abstractions from Service Oriented Architecture Artifacts

Rule-based methods have traditionally been applied to develop knowledge-based systems that replicate expert performance on a deep but narrow problem domain. Knowledge engineers capture expert knowledge and encode it as a set of rules for automating the expert’s reasoning process to solve problems in a variety of domains. We describe the development of a knowledge-based system approach to enhance program comprehension of Service Oriented Architecture (SOA) software. Our approach uses rule-based methods to automate the analysis of the set of artifacts involved in building and deploying a SOA composite application. The rules codify expert knowledge to abstract information from these artifacts to facilitate program comprehension and thus assist Software Engineers as they perform system maintenance activities. A main advantage of the knowledge-based approach is its adaptability to the heterogeneous and dynamically evolving nature of SOA environments.

Privacy Protection Framework with Defined Policies for Service-Oriented Architecture

Service-Oriented Architecture (SOA) is a computer systems design concept which aims to achieve reusability and inte- gration in a distributed environment through the use of autonomous, loosely coupled, interoperable abstractions known as services. In order to interoperate, communication between services is very important due to their autonomous nature. This communication provides services with their functional strengths, but also creates the opportunity for the loss of privacy. In this paper, a Privacy Protection Framework for Service-Oriented Architecture (PPFSOA) is described. In this framework, a Privacy Service (PS) is used in combination with privacy policies to create privacy contracts that out- line what can and cannot be done with a consumer's personally identifiable information (PII). The privacy policy con- sists of one-to-many privacy rules, with each rule created from a set of six privacy elements: collector, what, purpose, retention, recipient and trust. The PS acts as an intermediary between the service consumer and service provider, to es- tablish an unbiased contract before the two parties begin sending PII. It is shown how many Privacy Services work to- gether to form the privacy protection framework. An examination of what current approaches to protecting privacy in an SOA environment is also presented. Finally, the operations the PS must perform in order to fulfill its tasks are out- lined.

Resource management of distributed virtual machines

Using Virtual Machines (VMs) as a computing resource within a Service Oriented Architecture (SOA) creates a variety of new issues and challenges. Traditionally parallel task scheduling algorithms only focus on handling CPU resources but with use of a VM there are many more resources properties to monitor and manage. The objective of this paper is to address these challenges of a multi–dimensional scheduling algorithm for VMs within a SOA. To do this we deploy a testbed of SOA environment with VMs that are capable of being registered, indexed, allocated, accessed and controlled by our new parallel task scheduling algorithms.

A CACHING TECHNIQUE FOR OPTIMIZING AUTOMATED SERVICE DISCOVERY

The development of sophisticated technologies for service-oriented architectures (SOA) is a grand challenge. A promising approach is the employment of semantic technologies to better support the service usage cycle. Most existing solutions show significant deficits in the computational performance, which hampers the applicability in large-scale SOA systems. We present an optimization technique for automated service discovery — one of the central operations in semantically enabled SOA environments — that can ensure a sophisticated performance while maintaining a high retrieval accuracy. The approach is based on goals that formally describe client objectives, and it employs a caching mechanism for enhancing the computational performance of a two-phased discovery framework. At design time, the suitable services for generic and reusable goal descriptions are determined by semantic matchmaking. The result is captured in a continuously updated graph structure that organizes goals and services with respect to the requested and provided functionalities. This is exploited at runtime in order to detect the suitable services for concrete client requests with minimal effort. We formalize the approach within a first-order logic framework, and define the graph structure along with the associated storage and retrieval algorithms. An empirical evaluation shows that significant performance improvements can be achieved.

A Scalable Framework for Policy-based QoS Management in SOA Environments

The successful integration of the Service Oriented Architecture (SOA) in large distributed environments greatly depends on their support of quality of service (QoS) management. The aim of QoS management is to guarantee diverse QoS levels to users issuing requests from a variety of platforms and underlying networks. In this paper, we present our policy-based framework for QoS management in SOA environment with both usual and mobile users. The framework is based on a federation of QoS Brokers that are in charge of mediating between service requestors and service providers, and carrying out various QoS management operations. We describe an auction-based ranking algorithm of functionally equivalent services, which ranks services according to their ability to fulfill the service requestor QoS requirements. The brokers are also in charge of handling appropriately service requests from mobile users equipped with various handheld devices.

Automatic Determination of Compatibility in Evolving Services

A major advantage of Service-Oriented Architectures (SOA) is composition and coordination of loosely coupled services. Because the development lifecycles of services and clients are de-coupled, multiple service versions must be maintained to support older clients. Typically versions are managed within the SOA by updating service descriptions using conventions on version numbers and namespaces. In all cases, the compatibility among services descriptions must be evaluated, which can be hard, error-prone and costly if performed manually, particularly for complex descriptions. In this paper, the authors describe a method to automatically determine when two service descriptions are backward compatible. The authors describe a case study to illustrate version compatibility information in a SOA environment and present initial performance overheads. By automatically exploring compatibility information, a) service developers can assess the impact of proposed changes; b) proper versioning requirements can be put in client implementations guaranteeing that incompatibilities will not occur during run-time; and c) messages exchanged in the SOA can be validated to ensure that only expected messages or compatible ones are exchanged.

A New Method for Service Binding in Service Oriented Architecture Using Auction Algorithm

One of the important debates in service-oriented architecture is the competitive conditions in the side of service provider and service consumer. In service-oriented architecture environment, different service consumers are trying to obtain their required service for which they compete with other service applicants. On the other hand different service providers are competing with each other to give services to the applicants, each trying to give their service upon more profit. In such ground the assignment of service provider to service consumer is critically important. In this paper we are searching for a solution by which assignment of service providers to service consumers would bring satisfaction for architectural elements so the service providers need for reassignment will decrease. To this end we present Auction Algorithm based assignment.

Identity management in GRID computing and Service Oriented Architectures: research and practice

Today, Service-Oriented Architecture (SOA) and Grid and Cloud computing comprise the key technologies in distributed systems. In systems following the SOA approach, functionalities are delivered and consumed as services. Given the variety of resources (i.e. data, computing capabilities, applications, etc) as well as the variation of user-requested Quality of Service (e.g., high performance, fast access, low cost, high media resolution, etc), there is a need for advanced user management, trust establishment and service management mechanisms which adjust, monitor and evaluate service provision according to the users’ requirements and rights. Within this context, security and privacy requirements have become of great importance, as well the need for flexible and efficient identity management. This editorial of the special issue “Identity Management in Grid and SOA” discusses the importance of identity management within SOA and Grid environments. A number of techniques and existing systems addressing these issues are presented and evaluated. Identity management is considered in various contexts and at different levels, including service composition level, system level and inter-system communication level.

A Petri Nets based functional validation for services composition

The service-oriented architecture (SOA) has been quite prevailing in enterprise applications development, integration, and deployment. In SOA environment, the complex problem can be solved by combining available individual services and ordering them to best suit their problem requirements. Service composition accelerates rapid enterprise application development, service reuse, and complex service consummation. Along with its dissemination, a potential – inevitable but must-be-overcome – problem is lack of interoperability among services as well as poor integrity and quality of individual ones. There are many existing approaches to compose service composition, ranging from abstract methods to those aiming to be industry standards (e.g. BPEL, BPSS, WSFL, etc.). However, they have been biased to define the SOA technology to create service composition. Explicitly, few approaches have concerned to the service composition at design time. Consequently, there is an urgent need for a systematic approach to assure integrity and interoperability in service composition at design time. In this paper, we utilize a functional validation to check the seamless connectivity between individual services to be composed and to represent services’ interdependency (e.g., invocation precedence) in a Petri Nets with reachability analysis and each service’s semantic description (e.g., functionality and role, input/output data definition, QoS metrics and values). This approach can be further used as a service composition validation methodology and an input to quality assessment, either as is or with augmentation.

A multi-language service-oriented architecture using an enterprise service bus

An Enterprise Service Bus (ESB) provides developers a platform for the straightforward development of a multi-language Service-Oriented Architecture (SOA). Mule, an open source ESB, is presented as one such ESB that easily provides a multi-language SOA integration solution. This paper offers a Mule 1.4 ESB configuration allowing the communication between web services written in Java and Ada running on the Ada Web Server as an example. Additionally, the example demonstrates the use of SOAP and REST style messages within the SOA environment.

웹 서비스 코레오그라피를 이용한 자동 웹 서비스 컴포지션 시스템

웹 서비스와 SOA(Service Oriented Architecture)의 확산으로 웹 서비스 컴포지션의 대한 관심도 점차 커져가고 있다. 최근에는 보다 동적이고 지능적인 SOA 환경의 구축을 위해서 자동 웹 서비스 컴포지션에 대한 연구가 활발하게 진행되고 있다. 하지만, 아직까지 자동 웹 서비스 컴포지션에 관한 완전한 해결책은 제시되지 못하고 있으며, 기존의 연구에서는 여러 가지 문제점을 드러내고 있다. 문법적인 정보 기반의 자동 컴포지션은 잘못된 의미 연결로 인하여 컴포지션의 정확성을 떨어뜨린다. 또한 대부분의 연구에서는 추상적인 컴포지션 결과를 만들어내기 때문에, 실제로 실행하기는 어려움이 있다. 본 논문에서는 이러한 문제점들을 개선하기 위하여 웹 서비스 코레오그라피 기반의 자동 웹 서비스 컴포지션 시스템을 제안하고 있다. 제안하는 시스템에서는 컴포지션의 정확성을 향상시켰고, 보다 구체적인 컴포지션 결과를 만들어낼 수 있다. Web Services composition has gained a considerable attention because of the widespread use of the Web Services and SOA. Recently, various researches on automatic Web Services composition are on going to realize more dynamic and intelligent SOA environments. However, there is no complete solution for automatic Web Services composition now and previous researches have several problems. Automatic composition based on syntactic information has low correctness through incorrect semantic linking. Moreover, many researches make an process as the result of composition which is hard for actual execution. In this paper, improved automatic Web Services composition based on Web Services choreography is proposed. In this system, the correctness is improved and the result of composition is more concrete process.

Quality of Service in SOA Environments. An Overview and Research Agenda (Quality of Service in SOA-Umgebungen)

Summary Interoperability and componentization are the two defining characteristics of Service Oriented Architectures (SOA). From a middleware perspective this means standardized quality of service (QoS) protocols and QoS-rich service descriptions. This paper provides an architectural overview of quality of service issues in SOA environments and a review of open problems and current research directions.

Building DAM solutions for service-oriented architecture

Service-oriented architecture (SOA) has become a tidal wave in the information technology world. But what expectations does this surge place on DAM vendors? What implications does it present for analyzing and acquiring DAM to fit within an SOA environment? How can DAM pilot projects be adapted to deliver on SOA requirements? What types of results can be delivered in a DAM SOA pilot? This paper will discuss methods to specify requirements, business workflows and pilot scenarios for DAM applications when you know that the answer for an enterprise is SOA. Real-world results from a DAM SOA pilot will also be reviewed.

Collaborative software design in an SOA environment

Based on the current Service-Oriented Architecture (SOA), this paper proposes a new collaborative software design methodology in an SOA Environment: the Global Software Enterprise (GSE). The current SOA is producer-centric, in which the service providers publish services that they produce and let the consumers to search available services to compose their applications. GSE is build on top of Consumer-Centric SOA (CCSOA), in which the application builders publish their application requirements for the service providers to follow when producing or customizing services to support the application. This new methodology reduces the workload and improves the application description capability of the service consumers. It also extends the capacity of design and code sharing, and thus further improves the software productivity. This paper presents the concepts, architecture, enabling techniques, and illustrative examples of collaborative software design in GSE.