Microservice Transition and its Granularity Problem: A Systematic Mapping Study

Microservices have gained wide recognition and acceptance in software industries as an emerging architectural style for autonomic, scalable, and more reliable computing. The transition to microservices has been highly motivated by the need for better alignment of technical design decisions with improving value potentials of architectures. Despite microservices' popularity, research still lacks disciplined understanding of transition and consensus on the principles and activities underlying "micro-ing" architectures. In this paper, we report on a systematic mapping study that consolidates various views, approaches and activities that commonly assist in the transition to microservices. The study aims to provide a better understanding of the transition; it also contributes a working definition of the transition and technical activities underlying it. We term the transition and technical activities leading to microservice architectures as microservitization. We then shed light on a fundamental problem of microservitization: microservice granularity and reasoning about its adaptation as first-class entities. This study reviews state-of-the-art and -practice related to reasoning about microservice granularity; it reviews modelling approaches, aspects considered, guidelines and processes used to reason about microservice granularity. This study identifies opportunities for future research and development related to reasoning about microservice granularity.Comment: 36 pages including references, 6 figures, and 3 table

Code Generation Techniques for Developing Light-Weight XML Web Services for Embedded Devices

This paper presents specialized code generation techniques and runtime optimizations for developing light-weight XML Web services for embedded devices. The optimizations are implemented in the gSOAP Web services development environment for C and C++. The system supports the industry-standard XML-based Web services protocols that are intended to deliver universal access to any networked application that supports XML. With the standardization of the Web services protocols and the availability of toolkits such as gSOAP for developing embedded Web services, new opportunities emerge to integrate embedded systems into larger frameworks of interconnected applications and systems accessing dynamic resources on the Web ranging from handheld and embedded devices to databases, clusters, and Grids

Uma arquitetura baseada em web services com diferenciação de serviços para integração de sistemas embutidos a outros sistemas

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da ComputaçãoTecnologias para integração de sistemas, como Web Services, vêm sendo empregadas com sucesso para integração de softwares empresariais, permitindo a interação entre sistemas utilizados em diferentes organizações. Web Services têm se mostrado uma arquitetura eficiente para a interconexão de sistemas através da rede. Sistemas Embutidos estão cada vez mais integrados à Internet através da interconexão destes dispositivos em redes TCP/IP. E a integração de aplicações provenientes dos Sistemas Embutidos a outros sistemas vem se mostrando, do mesmo modo, cada vez mais necessária. Este trabalho busca propor e apresentar uma arquitetura baseada em Web Services com diferenciação de serviços para integração de Sistemas Embutidos a outros sistemas. Portanto, realizamos uma definição de uma política de escalonamento com diferenciação entre os serviços e analisamos a adequação da arquitetura de Web Services e da infra-estrutura desenvolvida neste trabalho para a integração de aplicações desenvolvidas sobre sistemas embutidos. A implantação desta arquitetura foi alcançada através do estudo, da modelagem e desenvolvimento do suporte para execução de web services projetados com o toolkit gSOAP tendo como ambiente o sistema embutido SHIP, identificando as limitações para sua integração com outros dispositivos. Ao longo deste trabalho, realizamos mudanças no firmware deste dispositivo com o intuito de permitir a sua integração através do uso de Web Services, e também criamos uma extensão ao toolkit gSOAP para que este oferecesse suporte a diferenciação de serviços. Através da implementação dos serviços usados como testes, conseguimos demonstrar que podemos disponibilizar uma plataforma para o desenvolvimento de Web Services em sistemas embutidos, tanto em relação ao desempenho, quanto ao classificador de serviços proposto, sendo viável para um conjunto significativo de aplicações com restrições temporais do tipo melhor-esforço e de tempo real brando (soft). System integration technologies, such as Web Services, have been employed successfully for the integration of business software, allowing the interaction between systems hosted by different companies. Web Services has shown an efficient architecture for the interconnection of systems through the net. Embedded Systems are more integrated to the Internet through the interconnection of these devices in TCP/IP nets. And the integration of applications proceeding from the Embedded Systems to other systems, in a similar way, becomes more necessary. This work seeks to propose and to present an architecture based on Web Services with services differentiation for Embedded Systems integration to other systems. Therefore, we made a scheduling politics definition with differentiation between the services and analyze the adequacy of the Web Services architecture and the infrastructure developed in this work for the integration of applications developed on Embedded systems. The implantation of this architecture was reached through the study, modeling and development of a web services execution support projected with the gSOAP toolkit having as embedded system environment the SHIP board, identifying the limitations for its integration with other devices. Along these work, we made changes in the firmware of these device in order to allow their integration through the use of Web Services, and also we create an gSOAP#s toolkit extension to provide services differentiation support. Through the services implementation used as tests, we demonstrate that we can provide a platform for the development of Web Services in Embedded Systems, achieving performance and classifying services, being viable for a significant set of applications with time constraints such as best-effort and soft real-time

Suporte de monitorização baseada em NETCONF

Mestrado em Engenharia de Computadores e TelemáticaA necessidade de gestão dos equipamentos das redes tem juntado em volta de organismos normalizadores como o IETF e o DMTF, a comunidade académica e os fabricantes de equipamentos. A evolução das características das redes, como por exemplo a sua dimensão, o número e a heterogeneidade dos equipamentos interligados, e a crescente diversidade de serviços de rede têm vindo a alterar os requisitos de gestão e, por conseguinte, a criar a necessidade de novas tecnologias para gerir essas redes. A tecnologia de gestão SNMP surgiu em meados dos anos 80 e, apesar de um conjunto de defeitos que rapidamente lhe foram apontados, rapidamente se tornou a tecnologia de gestão de facto, sendo omnipresente na maioria dos equipamentos de rede e estando disponível sob a forma de imensas APIs e aplicações de gestão. Sendo uma tecnologia nascida de entre a comunidade de gestão de redes IP, não incluía outros detalhes relacionados com a gestão de sistemas e serviços que entretanto foram incluídos pelo DMTF na tecnologia WBEM, segundo uma lógica de gestão integrada. O WBEM inclui já tecnologias da web para representar e codificar a informação de gestão, de forma a fomentar a interoperabilidade da gestão dos equipamentos de diferentes modelos e fabricantes. Com o advento dos Web services, e dada as suas vantagens de rápido desenvolvimento e interoperabilidade, as entidades normalizadoras da área da gestão dos sistemas propuseram novas tecnologias como o WSDM-MUWS do OASIS e o WS-MAN do DMTF. Como forma de ultrapassar os problemas desde sempre apontados ao SNMP, especialmente os relacionados com a sua segurança e falta de escalabilidade para transporte de grandes quantidade de informação, o IETF desenvolveu uma nova tecnologia designada de NETCONF que utiliza a codificação XML e alternativas de transporte de informação seguras e fiáveis. Normalizou também uma linguagem para descrição da informação de gestão, o YANG, criada especificamente para ser utilizada com este protocolo. Neste trabalho, implementou-se uma solução de monitorização utilizando a tecnologia NETCONF, que efetua o transporte da informação de gestão em SOAP. A presente dissertação documenta a implementação da solução de monitorização NETCONF proposta e da respetiva avaliação, comparado as características e capacidades da tecnologia utilizada com as tecnologias de gestão SNMP e WBEM em termos de tráfego gerado, de eficiência de sinalização e de tempos de resposta. Da análise destes testes são tiradas ilações acerca do desempenho destes protocolos e da viabilidade do NETCONF como solução futura para a gestão e monitorização de redes.The need for management of network equipment has gathered around standard setting bodies like the IETF and the DMTF, the academic community and equipment manufacturers. The evolution of network characteristics such as its size, the number and heterogeneity of devices, and the growing diversity of network services are changing the management requirements and, therefore creating the need for new technologies to manage these networks. The SNMP management technology emerged in the mid 80s and, despite a number of defects that were pointed out, it quickly became the de facto management technology, is ubiquitous in most network equipment and is available in lots of APIs and management applications. Being a technology born from IP network management community, it did not include other details related to the management of systems and services which have been included in the DMTFs WBEM standard, for integrated management. WBEM already includes web-based technologies to represent and encode management information in order to enhance interoperability among the solutions and equipment from different manufacturers. With the advent of Web services, and given its advantages of rapid development and interoperability, entities standardizing management systems proposed new technologies such as the OASIS WSDM-MUWS and the DMTF WS-MAN. To overcome the problems pointed to SNMP, especially those related to its safety and lack of scalability to transport large amount of information, the IETF has developed a new technology called NETCONF that uses the XML encoding and several alternatives for secure and reliable transport of information. They also normalized a language for describing management information, YANG, created specifically for use with this protocol. In this work, we implemented a monitoring solution using NETCONF, which makes the transport of management information in SOAP. This dissertation documents this implementation, the relevant technical assessment of the proposal and compared the features and capabilities of the technology used with the WBEM and SNMP technologies in terms of generated traffic, coding efficiency and response times. From the analysis of these tests lessons are taken about the performance of these protocols and the feasibility of NETCONF as a solution for the future of network management and monitoring

Engineering framework for service-oriented automation systems

Tese de doutoramento. Engenharia Informática. Universidade do Porto. Faculdade de Engenharia. 201

Web service control of component-based agile manufacturing systems

Current global business competition has resulted in significant challenges for manufacturing and production sectors focused on shorter product lifecyc1es, more diverse and customized products as well as cost pressures from competitors and customers. To remain competitive, manufacturers, particularly in automotive industry, require the next generation of manufacturing paradigms supporting flexible and reconfigurable production systems that allow quick system changeovers for various types of products. In addition, closer integration of shop floor and business systems is required as indicated by the research efforts in investigating "Agile and Collaborative Manufacturing Systems" in supporting the production unit throughout the manufacturing lifecycles. The integration of a business enterprise with its shop-floor and lifecycle supply partners is currently only achieved through complex proprietary solutions due to differences in technology, particularly between automation and business systems. The situation is further complicated by the diverse types of automation control devices employed. Recently, the emerging technology of Service Oriented Architecture's (SOA's) and Web Services (WS) has been demonstrated and proved successful in linking business applications. The adoption of this Web Services approach at the automation level, that would enable a seamless integration of business enterprise and a shop-floor system, is an active research topic within the automotive domain. If successful, reconfigurable automation systems formed by a network of collaborative autonomous and open control platform in distributed, loosely coupled manufacturing environment can be realized through a unifying platform of WS interfaces for devices communication. The adoption of SOA- Web Services on embedded automation devices can be achieved employing Device Profile for Web Services (DPWS) protocols which encapsulate device control functionality as provided services (e.g. device I/O operation, device state notification, device discovery) and business application interfaces into physical control components of machining automation. This novel approach supports the possibility of integrating pervasive enterprise applications through unifying Web Services interfaces and neutral Simple Object Access Protocol (SOAP) message communication between control systems and business applications over standard Ethernet-Local Area Networks (LAN's). In addition, the re-configurability of the automation system is enhanced via the utilisation of Web Services throughout an automated control, build, installation, test, maintenance and reuse system lifecycle via device self-discovery provided by the DPWS protocol...cont'd

A web services based framework for efficient monitoring and event reporting.

Network and Service Management (NSM) is a research discipline with significant research contributions the last 25 years. Despite the numerous standardised solutions that have been proposed for NSM, the quest for an "all encompassing technology" still continues. A new technology introduced lately to address NSM problems is Web Services (WS). Despite the research effort put into WS and their potential for addressing NSM objectives, there are efficiency, interoperability, etc issues that need to be solved before using WS for NSM. This thesis looks at two techniques to increase the efficiency of WS management applications so that the latter can be used for efficient monitoring and event reporting. The first is a query tool we built that can be used for efficient retrieval of management state data close to the devices where they are hosted. The second technique is policies used to delegate a number of tasks from a manager to an agent to make WS-based event reporting systems more efficient. We tested the performance of these mechanisms by incorporating them in a custom monitoring and event reporting framework and supporting systems we have built, against other similar mechanisms (XPath) that have been proposed for the same tasks, as well as previous technologies such as SNMP. Through these tests we have shown that these mechanisms are capable of allowing us to use WS efficiently in various monitoring and event reporting scenarios. Having shown the potential of our techniques we also present the design and implementation challenges for building a GUI tool to support and enhance the above systems with extra capabilities. In summary, we expect that other problems WS face will be solved in the near future, making WS a capable platform for it to be used for NSM

Ressourcen Optimierung von SOA-Technologien in eingebetteten Netzwerken

Embedded networks are fundamental infrastructures of many different kinds of domains, such as home or industrial automation, the automotive industry, and future smart grids. Yet they can be very heterogeneous, containing wired and wireless nodes with different kinds of resources and service capabilities, such as sensing, acting, and processing. Driven by new opportunities and business models, embedded networks will play an ever more important role in the future, interconnecting more and more devices, even from other network domains. Realizing applications for such types of networks, however, is a highly challenging task, since various aspects have to be considered, including communication between a diverse assortment of resource-constrained nodes, such as microcontrollers, as well as flexible node infrastructure. Service Oriented Architecture (SOA) with Web services would perfectly meet these unique characteristics of embedded networks and ease the development of applications. Standardized Web services, however, are based on plain-text XML, which is not suitable for microcontroller-based devices with their very limited resources due to XML's verbosity, its memory and bandwidth usage, as well as its associated significant processing overhead. This thesis presents methods and strategies for realizing efficient XML-based Web service communication in embedded networks by means of binary XML using EXI format. We present a code generation approach to create optimized and dedicated service applications in resource-constrained embedded networks. In so doing, we demonstrate how EXI grammar can be optimally constructed and applied to the Web service and service requester context. In addition, so as to realize an optimized service interaction in embedded networks, we design and develop an optimized filter-enabled service data dissemination that takes into account the individual resource capabilities of the nodes and the connection quality within embedded networks. We show different approaches for efficiently evaluating binary XML data and applying it to resource constrained devices, such as microcontrollers. Furthermore, we will present the effectful placement of binary XML filters in embedded networks with the aim of reducing both, the computational load of constrained nodes and the network traffic. Various evaluation results of V2G applications prove the efficiency of our approach as compared to existing solutions and they also prove the seamless and successful applicability of SOA-based technologies in the microcontroller-based environment