Service-oriented Architecture Services Research Articles

Services interfaces for interoperability of signaling computer interlocking on borders

<p>Technological developments in the field of railway signaling have allowed more and more flexibility in the management of rail traffic, especially with computer interlocking. However, differences in signaling principles from one country to another as well as differences in the structure of interlocking software and communication protocols depending on suppliers lead to interoperability difficulties at the borders between computer interlocking. Some deployed projects deal with interoperability issues regarding the communication of signaling information between the train and interlocking like the European rail traffic management system (ERTMS) project. Unfortunately, the interoperability between interlocking themselves is still not achieved. Some deployed projects deal with interoperability issues regarding the communication of signaling information between the train and interlocking like the ERTMS project. Unfortunately, the interoperability between interlocking themselves is still not achieved. This article draws up a proposed model for interfacing at the interlocking boundaries based on service-oriented architecture (SOA). In addition, to ensure the coupling of SOA services to the internal functions of the signaling computer interlocking, a distributed architecture of programmable logic controller according to the IEC 61499 standard is suggested.</p>

Patterns for Migration of SOA Based Applications to Microservices Architecture

Service oriented architecture (SOA) has been widely used in the design of enterprise applications over the last two decades. Though SOA has become popular in the integration of multiple applications using the enterprise service bus, there are few challenges related to delivery, deployment, governance, and interoperability of services. To overcome the design and maintenance challenges in SOA, a new architecture of microservices has emerged with loose coupling, independent deployment, and scalability as its key features. With the advent of microservices, software architects have started to migrate legacy systems to microservice architecture. However, many challenges arise during the migration of SOA to microservices, including the decomposition of SOA to microservice, the testing of microservices designed using different programming languages, and the monitoring the microservices. In this paper, we aim to provide patterns for the most recurring problems highlighted in the literature i.e, the decomposition of SOA services, the size of each microservice, and the detection of anomalies in microservices. The suggested patterns are combined with our experience in the migration of SOA-based applications to the microservices architecture, and we have also used these patterns in the migration of other SOA applications. We evaluated these patterns with the help of a standard web-based application.

Performance and complexity comparison of service oriented architecture and microservices architecture

Microservices has emerged as a new architectural style of designing applications to overcome the challenges of service oriented architecture (SOA). With the evolution of microservices architecture, architects have started migrating legacy applications to microservices. However, some of the architects are in chaos whether to migrate the application from SOA to microservices or not. The need for empirical evaluation and comparison of both the SOA and microservices architecture is also on-demand. This work helps the software architects in better understanding of the technical differences between both styles. We, therefore, present a comparison of a web application that is designed using both SOA and microservices architectures. The comparison is presented with two different parameters: 1) complexity with architectural metrics; 2) performance with load testing. It is clear from the results that though the complexity of microservices architecture is high, the response time for processing the requests is very fast compared to SOA services.

ReSIde: Reusable service identification from software families

The clone-and-own approach becomes a common practice to quickly develop Software Product Variants (SPVs) that meet variability in user requirements. However, managing the reuse and maintenance of the cloned codes is a very hard task. Therefore, we aim to analyze SPVs to identify cloned codes and package them using a modern systematic reuse approach like Service-Oriented Architecture (SOA). The objective is to benefit from all the advantages of SOA when creating new SPVs. The development based on services in SOA supports the software reuse and maintenance better than the development based on individual classes in monolithic object-oriented software. Existing service identification approaches identify services based on the analysis of a single software product. These approaches are not able to analyze multiple SPVs to identify reusable services of cloned codes. Identifying services by analyzing several SPVs allows to increase the reusability of identified services. In this paper, we propose ReSIde (Reusable Service Identification): an automated approach that identifies reusable services from a set of object-oriented SPVs. This is based on analyzing the commonality and the variability between SPVs to identify the implementation of reusable functionalities corresponding to cloned codes that can be packaged as reusable services. To validate ReSIde, we have applied it on three product families of different sizes. The results show that the services identified based on the analysis of multiple product variants using ReSIde are more reusable than services identified based on the analysis of singular ones.

Integrating recurrent neural networks and reinforcement learning for dynamic service composition

In the service oriented architecture (SOA), software and systems are abstracted as web services to be invoked by other systems. Service composition is a technology, which builds a complex system by combining existing simple services. With the development of SOA and web service technology, massive web services with the same function begin to spring up. These services are maintained by different organizations and have different QoS (Quality of Service). Thus, how to choose the appropriate service to make the whole system to deliver the best overall QoS has become a key problem in service composition research. Furthermore, because of the complexity and dynamics of the network environment, QoS may change over time. Therefore, how to adjust the composition system dynamically to adapt to the changing environment and ensure the quality of the composed service also poses challenges. To address the above challenges, we propose a service composition approach based on QoS prediction and reinforcement learning. Specifically, we use a recurrent neural network to predict the QoS, and then make dynamic service selection through reinforcement learning. This approach can be well adapted to a dynamic network environment. We carry out a series of experiments to verify the effectiveness of our approach.

Efficient Device-to-Device Service Invocation Using Arrowhead Orchestration

The Internet of Things (IoT) enables interaction from real-world physical objects using sensors to the virtual world of computers and the Internet. The use of service-oriented architecture (SOA) is one step in the creation of basic and complex interactions between several sensors and actuators. However, the use of SOA-enabled technologies alone does not meet all requirements of how sensor and actuator systems could be integrated to create distributed monitoring and control applications. The centralized, traditional method of communication in wireless sensor networks via a gateway presents drawbacks that have to be addressed; device-to-cloud communication adds higher latency and higher power consumption and is less robust than the device-to-device (D2D) communication approach. Moreover, all these characteristics reduce the scalability of the network, thus limiting the use of IoT in the industry. In this article, the proposed method utilizes the arrowhead framework orchestration system to generate service composition within a (wireless) network formed by IoT devices. The aim is to achieve efficient D2D service invocation to reduce the drawbacks of today’s widely used device-to-cloud approach. The method in this article performs efficient service composition for industrial IoT, including mapping SOA service composition in very small resource-constrained devices using the arrowhead orchestration. The results presented in this article at the service level can increase performance and robustness in fog computing on resource-constrained devices.

BPMN 기반 경로 탐색을 이용한 테스트 케이스 생성 기법

SOA (Service Oriented Architecture)를 기반으로 하는 소프트웨어는 비즈니스 요구사항에 기민하게 대응할 수 있어 사용이 확대되고 있다. SOA는 느슨한 서비스 결합과 메시지 교환 중심 아키텍처라는 특징 때문에 기존의 테스팅 방법 적용이 제한된다. 본 논문에서는 BPMN (Business Process Model and Notation)을 이용해 테스트 케이스를 생성하는 기법을 제안한다. 먼저 프로세스를 모델링하고, 이를 통해 비즈니스 흐름 그래프(BFG)를 생성한다. BFG의 입출력 차수를 대칭하고, 오일러 경로를 탐색하여 테스트 케이스를 생성한다. BPMN을 이용한 테스트 케이스 생성 기법은 SOA 기반 시스템에 적용 가능하며, 테스트 케이스 수를 감소시킬 수 있다. The SOA (Service Oriented Architecture) based softwares are escalated because of quickly coping with business requirement. SOA can not apply to existing test method because of loosely coupled service and massage exchange architecture. In this paper, we suggest a method of test case generation using BPMN (Business Process Model and Notation). First we model processes, then make Business Flow Graph (BFG). After searching the euler path through symmetrized BFG about input and output degrees, we generate test cases. A method of test case generation using BPMN can apply at SOA-based system, and reduce the number of test cases.

Microservices tenets

Some microservices proponents claim that microservices form a new architectural style; in contrast, advocates of service-oriented architecture (SOA) argue that microservices merely are an implementation approach to SOA. This overview and vision paper first reviews popular introductions to microservices to identify microservices tenets. It then compares two microservices definitions and contrasts them with SOA principles and patterns. This analysis confirms that microservices indeed can be seen as a development- and deployment-level variant of SOA; such microservices implementations have the potential to overcome the deficiencies of earlier approaches to SOA realizations by employing modern software engineering paradigms and Web technologies such as domain-driven design, RESTful HTTP, IDEAL cloud application architectures, polyglot persistence, lightweight containers, a continuous DevOps approach to service delivery, and comprehensive but lean fault management. However, these paradigms and technologies also cause a number of additional design choices to be made and create new options for many "distribution classics" type of architectural decisions. As a result, the cognitive load for (micro-)services architects increases, as well as the design, testing and maintenance efforts that are required to benefit from an adoption of microservices. To initiate and frame the buildup of architectural knowledge supporting microservices projects, this paper compiles related practitioner questions; it also derives research topics from these questions. The paper concludes with a summarizing position statement: microservices constitute one particular implementation approach to SOA (service development and deployment).

On the Ex Ante Valuation of IT Service Investments

The paradigm of service orientation and its incarnation in the form of service-oriented architecture (SOA) and information technology (IT) services play a crucial role in enabling companies to achieve considerable competitive advantages. However, to be able to leverage the opportunities of SOA and IT services, companies need to gain a thorough understanding of the business value of IT service investments. Nevertheless, research on IT services has focused mainly on technical questions so far; the economic perspective largely has been neglected. Therefore, the authors aim to contribute to the ex ante valuation of IT service investments from a decision theoretical point of view. Using decision theory as a theoretical base, the main aim is to identify and discuss specific challenges regarding the financial ex ante valuation of IT service investments, which arise from the inherent flexibility of IT services and the various interdependencies within a company’s IT service portfolio. The authors thereby emphasize that the application of common methods from financial theory for valuating IT service investments has to be treated with caution, as these methods are often tied to rather restrictive assumptions based on the specifics of capital markets. By analyzing different clusters of IT service investment decision problems using decision theory, the authors identify and discuss pitfalls that might occur when applying financial valuation methods to capture the flexibility and interdependencies of IT service investments. The decision theoretical considerations are intended to help build a solid basis for future multi-criteria valuation approaches, of which an essential component is a theoretically well-founded financial valuation.

Synergy of Services within SOA

The enterprises need to react promptly and efficiently to any technological or economical demand, despite the fact that globalization causes different-nature challenges nowadays. One of the main technical issues is complicated heterogeneous systems. Mainly, these systems have grown over years, and caused different technological and economic problems. With introducing Service Oriented Architecture (SOA) and its services, it started to be possible for companies to operate against these complications. For this reason, we investigate in this paper the synergy challenges within SOA services, including Web-, Grid-, Peer-to-Peer-, and Cloud-related ones.

An Empirical Study on Testing of SOA based Services

Service-Oriented Architecture (SOA) removed the gap between software and business. Today, there is a business transformation among enterprises and they adopt a service based information technology (IT) model. So, testing is necessary for SOA based applications. This paper investigates different type of approaches and techniques that address the testing problems of SOA based services. Here we also investigate the differences between SOA and web services and traditional testing and SOA testing. Various testing levels are also discussed in detail. This paper also expresses various testing perspectives, challenges of SOA testing and review the many testing approaches and identify the problems that improve the testability of SOA based services.

Fifteen Years of Service-Oriented Architecture at Credit Suisse

Credit Suisse has been an adopter of service oriented architecture (SOA) principles and patterns since the beginnings of this architectural style, even before the term appeared. The authors reflect on the financial institution's journey from using tightly integrated mainframe programs to open SOA services, emphasizing the importance of interface contracts and service governance in corporate IT.

Toward A Full Implementation of the Operation and Support Subsystem (OSS) in IMS Networks

Recently, mobile operators all over the world are facing big challenges on the decreasing of the revenues from its traditional killer-applications like SMS/MMS and even voice services. The challenges come from a new trend of services called OTT (Over The Top). These OTT services provide the mobile users with flexible, convenient and more importantly free means to do their daily multimedia communication needs and seamlessly without any border so that operators couldn’t be just simply block it, but in opposite, need to find solutions to compete against it. Because of that, nowadays, more and more operators choose to deploy the standard RCS (Rich Communication Suite). RCS is a set of rich features communication services developed on top of IMS framework. Although there have been tremendous efforts to develop the architecture and protocols for IMS, which is a key technology of the NGN, it is far from being widely deployed. There are many reasons for that unpopularity (of IMS commercial deployment), namely, the lacking of clear business model for IMS-based services, no big difference between IMS-based services and SOA (Service Oriented Architecture) services, lack of the true demands for features that IMS based services have, etc... However, one of the most important reason that till now not many researchers have pointed out and addressed it, is about the OSS (Operation and Support Subsystem) functions. The lacking of OSS clearly defined functions and interfaces make the difficulties for operators and even equipment manufacturers to collect the pay back for any big scale IMS deployment for their networks. This paper presents our proven that IMS can provide the killer applications with blending features like mash-up and readily equipped with the intelligent charging and policy control functions. That may partly help to speed up the deployment process of IMS in real networking environment.

An Analysis of Application Level Security in Service Oriented Architecture

In computing, the software elements like objects and components emphasize on reusability using design tools of abstraction and separation of concerns. Software architecture has appeared as an initial idea to develop huge, complicated and heterogeneous distributed systems successfully. Service Oriented Architecture (SOA) combines services together to make systems having a greater impact on the way software systems are developed. SOA addresses the need of standards-based, loosely connected, and distributed computing which is protocol independent. It is not easy to ensure the secure transaction of data, where the movement of data occurs through loosely connected services. A number of techniques have been proposed in the contemporary literature to guide the SOA implementation in distributed system. These techniques offer certain benefits, but pose some challenges alongside such as the use of meta-data as framework and standard, contract documents, security patterns and security adviser, etc. The objective of this research is to provide a comprehensive analysis of various approaches used to provide application level security to the web services in SOA. These approaches have been compared based on a number of parameters. In addition, we critically evaluate different security methods used in SOA. The study also discusses some future directions in this domain.

Service-oriented Architecture Projects in Practice: A Study of a Shared Document Service Implementation

Abstract This paper reports on a case study focusing on service-oriented architecture (SOA) projects in practice. The aim of these projects has been to develop a shared document service supporting different business divisions in a large Norwegian governmental institution. The research question guiding this research is: How are SOA projects carried out in practice? What are the challenges of developing shared services in service-oriented architecture? SOA projects are accompanied by a complex socio-technical system development environment. In the present study we followed parallel system development processes and identified several issues associated with competence requirements, distributed coordination principles and control, lack of communication, tuning of parallel projects, and selection of appropriate project management approaches and system development methods. Clearly, there was a difference between undertaking a system development project within one organizational unit (silo) compared to the development of shared services to provide support across a large organization. Findings demonstrate that the complexity of SOA projects was underestimated by the project managers, and ad hoc governance was practiced in terms of control, coordination, and communication. To capture the entire system development context of an SOA project, a holistic approach and mind-set comprising time management and fine tuning of all parallel SD activities is necessary. Organizational maturity to carry out SOA projects is also of significance. The study has implications for SOA adopters in general and for system developers and project managers working in an SOA context in particular.

A Scalable Architecture for Automatic Service Composition

This paper addresses automatic service composition (ASC) as a means to create new value-added services dynamically and automatically from existing services in service-oriented architecture and cloud computing environments. Manually composing services for relatively static applications has been successful, but automatically composing services requires advances in the semantics of processes and an architectural framework that can capture all stages of an application's lifecycle. A framework for ASC involves four stages: planning an execution workflow, discovering services from a registry, selecting the best candidate services, and executing the selected services. This four-stage architecture is the most widely used to describe ASC, but it is still abstract and incomplete in terms of scalable goal composition, property transformation for seamless automatic composition, and integration architecture. We present a workflow orchestration to enable nested multilevel composition for achieving scalability. We add to the four-stage composition framework a transformation method for abstract composition properties. A general model for the composition architecture is described herein and a complete and detailed composition framework is introduced using our model. Our ASC architecture achieves improved seamlessness and scalability in the integrated framework. The ASC architecture is analyzed and evaluated to show its efficacy.

ERP System Implementation Based SOA under SaaS Model

In recent years, information management draws more and more attention. Various ERP systems have gradually emerged, and the development techniques of systems are becoming more flexible. With the increasing of complex business, there will be more demands on the flexibility, practicality and scalability of the system. In addition, especially for SMEs, management is more traditional, and it exits the shortcomings that the majority rely on previous management experience, have limited capital investment, and cannot have a dedicated IT personnel and so on, leading the usage patterns of the traditional software product beyond the capacity of SMEs. After analyzing the structure features of the service-oriented architecture (SOA) and Software as a Service (SaaS), the paper proposes ERP system based SOA. On this basis, the paper starts from the business process management (BPM), combines SOA and traditional enterprise service bus (ESB) to achieve the integration of ERP systems and combines SOA with SaaS to achieve the enterprise application of ERP systems for specific businesses.

ASBU기반의 항공데이터 종합관리망 테스트베드 구축방안

국제민간항공기구(ICAO)는 ASBU(Aviation System Block Upgrade)를 통해서 2013년부터 20년간 항공관련 데이터 시스템의 성능을 향상시키는 프로그램을 채택하였다. 프로그램의 일부분으로써 SWIM(System Wide Information Management) 기술 개발을 통한 항공통신 데이터를 종합 관리하는 망에 대한 연구개발은 미국, 유럽 선진국들을 중심으로 진행 중이다. 이에 따라, 본 논문에서는 선진국들의 개발 동향과 대등한 기술개발을 위해 SOA(Service Oriented Architecture) 개념을 적용한 항공 데이터 서비스 아키텍처 기술개발, 항공 데이터의 종합적 관리를 위한 미래형 데이터 관리 모델 개발, 기존의 항공 데이터 시스템과 연동을 위한 어댑터 기술 개발을 통하여 사용자 중심의 항공데이터 종합 관리망 기술을 개발하는 방법에 기반한 테스트베드 구축 방안을 제안한다. International Civil Aviation Organization adopted the program to improve performance of aviation-related data systems through the ASBU for 20 years from 2013. Research and development for integrated management network of aeronautical telecommunication data through SWIM(System Wide Information Management) technology which is part of program, are being progressed in the United States and European countries. Therefore, in this paper, we suggest a method of testbed implementation based on technology of aeronautical data services architecture applied the concept of SOA(Service Oriented Architecture), development of future data management model for integrated management of aeronautical data, and development of user-centric integrated aeronautical data management network through adapter technology for interoperating legacy aeronautical data system to develop even technology with development trends of advanced countries.

On description of contracts and agreements in the context of SOA

The issue of making contracts between services in Service-Oriented Architecture (SOA) arises naturally, because in real life services are subjects for negotiation and contracting. The notion of contract in SOA is rather misleading, because usually means just technical specification – input and output parameters, pre- and postconditions. However, there are also other aspects of contract. Service Level Agreements (SLAs) often are used together with technical contract. SLAs describes the level of service expected by a customer from a supplier, laying out the metrics by which that service is measured, the remedies or penalties in case the agreed-upon levels are not achieved. The paper aim to clear up the notions of contract and agreement in SOA, discusses the properties of languages that are used to specify contacts and agreements, paying special attention to their legal aspects and comparing contract features in WS-Agreement ir WSLA.

Computing Mode Study of Large-Scale Power Grid Online Analysis Software Based on Cloud Computing Technology

This paper construct a large-scale power grid online analysis architecture based on "'Dispatch Cloud' architecture and combined with the power system characteristics and large grid dispatch system online analysis software features, it propose power grid online analysis software wide-area multi-level distributed parallel computing mode based on Dispatch Cloud Platform which is service oriented architecture (SOA). In this mode the coordination manage needed is achieved in the way of service encapsulation based SOA, including, data and model management services, computing resource management services, the job management and parallel computing services, In this mode the coordination manage needed is achieved in the way of service encapsulation based on SOA, including, data and model management services, computing resource management services, the job management and parallel computing services. which will provide theoretical and technical support to the large-scale power grid Online analysis software design and development Using Cloud technology.