The Experts below are selected from a list of 15651 Experts worldwide ranked by ideXlab platform
Uwe Zdun - One of the best experts on this subject based on the ideXlab platform.
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supporting Architectural Decision making on data management in microservice architectures
European Conference on Software Architecture, 2019Co-Authors: Evangelos Ntentos, Uwe Zdun, Konstantinos Plakidas, Daniel Schall, Sebastian MeixnerAbstract:Today many service-based systems follow the microservice architecture style. As microservices are used to build distributed systems and promote architecture properties such as independent service development, polyglot technology stacks including polyglot persistence, and loosely coupled dependencies, architecting data management is crucial in most microservice architectures. Many patterns and practices for microservice data management architectures have been proposed, but are today mainly informally discussed in the so-called “grey literature”: practitioner blogs, experience reports, and system documentations. As a result, the Architectural knowledge is scattered across many knowledge sources that are usually based on personal experiences, inconsistent, and, when studied on their own, incomplete. In this paper we report on a qualitative, in-depth study of 35 practitioner descriptions of best practices and patterns on microservice data management architectures. Following a model-based qualitative research method, we derived a formal architecture Decision model containing 325 elements and relations. Comparing the completeness of our model with an existing pattern catalog, we conclude that our Architectural Decision model substantially reduces the effort needed to sufficiently understand microservice data management Decisions, as well as the uncertainty in the design process.
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guiding Architectural Decision making on service mesh based microservice architectures
European Conference on Software Architecture, 2019Co-Authors: Amine El Malki, Uwe ZdunAbstract:Microservices are becoming the de-facto standard way for software development in the cloud and in service-oriented computing. Service meshes have been introduced as a dedicated infrastructure for managing a network of containerized microservices, in order to cope with the complexity, manageability, and interoperability challenges in especially large-scale microservice architectures. Unfortunately so far no dedicated architecture guidance for designing microservices and choosing among technology options in a service mesh exist. As a result, there is a substantial uncertainty in designing and using microservices in a service mesh environment today. To alleviate this problem, we have performed a model-based qualitative in-depth study of existing practices in this field in which we have systematically and in-depth studied 40 reports of established practices from practitioners. In our study we modeled our findings in a rigorously specified reusable Architectural Decision model, in which we identified 14 Architectural design Decisions with 47 Decision outcomes and 77 Decision drivers in total. We estimated the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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ECSA - Guiding Architectural Decision Making on Service Mesh Based Microservice Architectures
Software Architecture, 2019Co-Authors: Amine El Malki, Uwe ZdunAbstract:Microservices are becoming the de-facto standard way for software development in the cloud and in service-oriented computing. Service meshes have been introduced as a dedicated infrastructure for managing a network of containerized microservices, in order to cope with the complexity, manageability, and interoperability challenges in especially large-scale microservice architectures. Unfortunately so far no dedicated architecture guidance for designing microservices and choosing among technology options in a service mesh exist. As a result, there is a substantial uncertainty in designing and using microservices in a service mesh environment today. To alleviate this problem, we have performed a model-based qualitative in-depth study of existing practices in this field in which we have systematically and in-depth studied 40 reports of established practices from practitioners. In our study we modeled our findings in a rigorously specified reusable Architectural Decision model, in which we identified 14 Architectural design Decisions with 47 Decision outcomes and 77 Decision drivers in total. We estimated the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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guiding Architectural Decision making on quality aspects in microservice apis
International Conference on Service Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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ICSOC - Guiding Architectural Decision Making on Quality Aspects in Microservice APIs
Service-Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
Olaf Zimmermann - One of the best experts on this subject based on the ideXlab platform.
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guiding Architectural Decision making on quality aspects in microservice apis
International Conference on Service Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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ICSOC - Guiding Architectural Decision Making on Quality Aspects in Microservice APIs
Service-Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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Architectural Decision guidance across projects problem space modeling Decision backlog management and cloud computing knowledge
IEEE IFIP International Conference on Software Architecture, 2015Co-Authors: Olaf Zimmermann, Heiko Koziolek, Lukas Wegmann, Thomas GoldschmidtAbstract:Architectural Knowledge Management (AKM) has been a major topic in software architecture research since 2004. Open AKM problems include an effective, seamless transition from reusable knowledge found in patterns books and technology blogs to project-specific Decision guidance and an efficient, practical approach to knowledge application and maintenance. We extended our previous work with concepts for problem space modeling, focusing on reusable knowledge, as well as solution space management, focusing on project-level Decisions. We implemented these concepts in AD Mentor, an extension of Sparx Enterprise Architect. AD Mentor features rapid problem space modeling, UML model linkage, question-option-criteria diagram support, meta-information for model tailoring, as well as Decision backlog management. We validated AD Mentor by modeling and applying 85 cloud application design Decisions and 75 workflow management Decisions, creating one problem and three sample solution spaces covering control system architectures, and obtaining user feedback on tool and model content.
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Architectural Decision identification in Architectural patterns
Proceedings of the WICSA ECSA 2012 Companion Volume on, 2012Co-Authors: Olaf ZimmermannAbstract:When modeling recurring Architectural Decisions for reuse, the boundaries of the knowledge asset under construction must be defined in a scoping step. This paper introduces and combines two supporting concepts for this step, pattern-centric Decision identification rules and generic meta issues; one particular meta issue catalog is also presented. The resulting general-purpose Decision identification method is validated by identifying 35 Decisions that recur in enterprise application development and service-oriented architecture design.
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WICSA/ECSA Companion Volume - Architectural Decision identification in Architectural patterns
Proceedings of the WICSA ECSA 2012 Companion Volume on - WICSA ECSA '12, 2012Co-Authors: Olaf ZimmermannAbstract:When modeling recurring Architectural Decisions for reuse, the boundaries of the knowledge asset under construction must be defined in a scoping step. This paper introduces and combines two supporting concepts for this step, pattern-centric Decision identification rules and generic meta issues; one particular meta issue catalog is also presented. The resulting general-purpose Decision identification method is validated by identifying 35 Decisions that recur in enterprise application development and service-oriented architecture design.
Ioanna Lytra - One of the best experts on this subject based on the ideXlab platform.
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Empirical evaluation of a process to increase consensus in group Architectural Decision making
Information and Software Technology, 2016Co-Authors: Dan Tofan, Uwe Zdun, Ioanna Lytra, Matthias Galster, Paris Avgeriou, Mark-anthony Fouche, Remco C. De Boer, F. SolmsAbstract:ContextMany software Architectural Decisions are group Decisions rather than Decisions made by individuals. Consensus in a group of Decision makers increases the acceptance of a Decision among Decision makers and their confidence in that Decision. Furthermore, going through the process of reaching consensus means that Decision makers understand better the Decision (including the Decision topic, Decision options, rationales, and potential outcomes). Little guidance exists on how to increase consensus in group Architectural Decision making. ObjectiveWe evaluate how a newly proposed process (named GADGET) helps architects increase consensus when making group Architectural Decisions. Specifically, we investigate how well GADGET increases consensus in group Architectural Decision making, by understanding its practical applicability, and by comparing GADGET against group Architectural Decision making without using any prescribed approach. MethodWe conducted two empirical studies. First, we conducted an exploratory case study to understand the practical applicability of GADGET in industry. We investigated whether there is a need to increase consensus, the effort and benefits of GADGET, and potential improvements for GADGET. Second, we conducted an experiment with 113 students from three universities to compare GADGET against group Architectural Decision making without using any prescribed approach. ResultsGADGET helps Decision makers increase their consensus, captures knowledge on Architectural Decisions, clarifies the different points of view of different Decision makers on the Decision, and increases the focus of the group discussions about a Decision. From the experiment, we obtained causal evidence that GADGET increases consensus better than group Architectural Decision making without using any prescribed approach. ConclusionsThere is a need to increase consensus in group Architectural Decisions. GADGET helps inexperienced architects increase consensus in group Architectural Decision making, and provides additional benefits, such as capturing rationale of Decisions. Future work is needed to understand and improve other aspects of group Architectural Decision making.
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reusable Architectural Decision models for quality driven Decision support a case study from a smart cities software ecosystem
Proceedings of the Third International Workshop on Software Engineering for Systems-of-Systems, 2015Co-Authors: Ioanna Lytra, Daniel Schall, Gerhard Engelbrecht, Uwe ZdunAbstract:Architectural design Decisions and Architectural knowledge are becoming relevant in the current practice of software architecture. In addition, reusable Architectural knowledge has gained much importance in the industrial practice. In the process of Architectural Decision making, quality attributes constitute key drivers for designing software systems, therefore, it is important to document quality attributes along with the Decisions captured. However, most of the current tools for management of Architectural Decisions focus mainly on capturing or sharing of design Decisions. We propose to enrich a reusable Architectural Decision meta-model with quality attributes and introduce a corresponding tool. Our goal is to support software architects during Decision making based on reusable Decisions driven by quality attributes. Our approach was motivated by and applied in an industrial case study on a large-scale software ecosystem for smart cities, that constitute a complex and challenging system-of-systems domain. We applied our proposal in a few scenarios in the smart cities domain, in which the consideration of quality attributes is required to model reusable Architectural knowledge adequately.
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Two controlled experiments on model-based Architectural Decision making
Information and Software Technology, 2015Co-Authors: Ioanna Lytra, Patrick Gaubatz, Uwe ZdunAbstract:We conduct controlled experiments concerning reusable Architectural Decision models.We measure the effect of Decision models on Decision making and documentation.Reusable Architectural Decision models increase the effectiveness of users.Reusable Architectural Decision models increase the efficiency of users.We discuss the inference of our results for Decision making by practitioners. ContextIn recent years, Architectural design Decisions are becoming more and more common for documenting software architectures. Rather than describing the structure of software systems, Architectural Decisions capture the design rationale and - often reusable - Architectural knowledge. Many approaches and tools have been proposed in the literature to support Architectural Decision making and documentation (for instance, based on models, ontologies, or templates). In this context, the capturing, organization, and effective reuse of Architectural knowledge has gained a lot of attention. ObjectiveHowever, there is little empirical evidence about the supportive effect of reusable Architectural knowledge on the effectiveness and efficiency of Architectural Decision making. MethodTo investigate these aspects, we conducted two separate controlled experiments with software architecture students in which we tested the supportive effect of reusable Decision models in Decision making and documentation. ResultsOur results show that the use of reusable Decision models can significantly increase both the efficiency and the effectiveness of novice architects. ConclusionWe can report, that our findings are in line with similar studies and support the claims regarding reusable Architectural design Decisions in principle.
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Automatic Enforcement of Constraints in Real-time Collaborative Architectural Decision Making
Journal of Systems and Software, 2015Co-Authors: Patrick Gaubatz, Ioanna Lytra, Uwe ZdunAbstract:Abstract Making and documenting Architectural design Decisions becomes increasingly important in the process of software architecting. However, the remoteness of different Decision stakeholders, ranging from local distribution in an office environment to globally distributed teams, as well as the different domain knowledge, expertise and responsibilities of the stakeholders hinder effective and efficient collaboration. Existing tools and methods for collaborative Architectural Decision making focus mainly on sharing and reusing of knowledge, making trade-offs, and achieving consensus, but do not consider the various stakeholders’ Decision making constraints due to their roles in the development process. To address this problem, we propose a meta-model for a set of Decision making constraints, with precisely defined semantics, as well as a collaborative Architectural Decision making approach based on this meta-model. We also present tool support, called CoCoADvISE, which automatically enforces the constraints at runtime. The evaluation of this tool in a controlled experiment with 48 participants shows that our approach, besides preventing constraint violations, significantly increases both the time and effort related efficiency, as well as the effectiveness of users in collaborative Decision making.
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SESoS@ICSE - Reusable Architectural Decision models for quality-driven Decision support: a case study from a smart cities software ecosystem
2015 IEEE ACM 3rd International Workshop on Software Engineering for Systems-of-Systems, 2015Co-Authors: Ioanna Lytra, Daniel Schall, Gerhard Engelbrecht, Uwe ZdunAbstract:Architectural design Decisions and Architectural knowledge are becoming relevant in the current practice of software architecture. In addition, reusable Architectural knowledge has gained much importance in the industrial practice. In the process of Architectural Decision making, quality attributes constitute key drivers for designing software systems, therefore, it is important to document quality attributes along with the Decisions captured. However, most of the current tools for management of Architectural Decisions focus mainly on capturing or sharing of design Decisions. We propose to enrich a reusable Architectural Decision meta-model with quality attributes and introduce a corresponding tool. Our goal is to support software architects during Decision making based on reusable Decisions driven by quality attributes. Our approach was motivated by and applied in an industrial case study on a large-scale software ecosystem for smart cities, that constitute a complex and challenging system-of-systems domain. We applied our proposal in a few scenarios in the smart cities domain, in which the consideration of quality attributes is required to model reusable Architectural knowledge adequately.
Cesare Pautasso - One of the best experts on this subject based on the ideXlab platform.
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guiding Architectural Decision making on quality aspects in microservice apis
International Conference on Service Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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ICSOC - Guiding Architectural Decision Making on Quality Aspects in Microservice APIs
Service-Oriented Computing, 2018Co-Authors: Uwe Zdun, Cesare Pautasso, Olaf Zimmermann, Mirko Stocker, Daniel LubkeAbstract:Microservice APIs represent the client perspective on microservice-based software architecture design and related practices. Major issues in API design concern the quality aspects of the API. However, it is not well understood today what the established practices related to those quality aspects are, how these practices are related, and what the major Decision drivers are. This leads to great uncertainty in the design process. In this paper, we report on a qualitative, in-depth study of 31 widely used APIs plus 24 API specifications, standards, and technologies. In our study we identified six recurring Architectural design Decisions in two API design contexts with a total of 40 Decision options and a total of 47 Decision drivers. We modelled our findings in a formal, reusable Architectural Decision model. We measured the uncertainty in the resulting design space with and without use of our model, and found that a substantial uncertainty reduction can be potentially achieved by applying our model.
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The blockchain as a software connector
Proceedings - 2016 13th Working IEEE IFIP Conference on Software Architecture WICSA 2016, 2016Co-Authors: Xiwei Xu, Babu Pillai, Alexander Ponomarev, Vincent Gramoli, Cesare Pautasso, An Binh Tran, Liming Zhu, Kamanashis Biswas, Vallipuram Muthukkumarasamy, Shiping ChenAbstract:—Blockchain is an emerging technology for decent-ralized and transactional data sharing across a large network of untrusted participants. It enables new forms of distributed software architectures, where components can find agreements on their shared states without trusting a central integration point or any particular participating components. Considering the block-chain as a software connector helps make explicitly important Architectural considerations on the resulting performance and quality attributes (for example, security, privacy, scalability and sustainability) of the system. Based on our experience in several projects using blockchain, in this paper we provide rationales to support the Architectural Decision on whether to employ a decentralized blockchain as opposed to other software solutions, like traditional shared data storage. Additionally, we explore spe-cific implications of using the blockchain as a software connector including design trade-offs regarding quality attributes.
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team situational awareness and Architectural Decision making with the software architecture warehouse
European Conference on Software Architecture, 2013Co-Authors: Marcin Nowak, Cesare PautassoAbstract:The core of the design of software architecture is all about Architectural Decision making. A high-quality design outcome sets high requirements, not only on the skills and knowledge of the design team members, but also on the management of the Decision making process. We claim that in order to deliver high quality Decisions, the design team needs to obtain a high level of situational awareness. To address this, we present an analysis of the problem of team situational awareness in design workshops and propose a model on how stakeholder positions help to build consensus within the argumentation viewpoint of Architectural Decisions. We show how the Software Architecture Warehouse tool has been extended to support the argumentation viewpoint within its live design document metaphor to provide support for co-located and distributed design workshops.
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ECSA - Team situational awareness and Architectural Decision making with the software architecture warehouse
Software Architecture, 2013Co-Authors: Marcin Nowak, Cesare PautassoAbstract:The core of the design of software architecture is all about Architectural Decision making. A high-quality design outcome sets high requirements, not only on the skills and knowledge of the design team members, but also on the management of the Decision making process. We claim that in order to deliver high quality Decisions, the design team needs to obtain a high level of situational awareness. To address this, we present an analysis of the problem of team situational awareness in design workshops and propose a model on how stakeholder positions help to build consensus within the argumentation viewpoint of Architectural Decisions. We show how the Software Architecture Warehouse tool has been extended to support the argumentation viewpoint within its live design document metaphor to provide support for co-located and distributed design workshops.
Nelly Schuster - One of the best experts on this subject based on the ideXlab platform.
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Managing Architectural Decision models with dependency relations, integrity constraints, and production rules
Journal of Systems and Software, 2009Co-Authors: Olaf Zimmermann, Frank Leymann, Jana Koehler, Ronny Polley, Nelly SchusterAbstract:Software architects consider capturing and sharing Architectural Decisions increasingly important; many tacit dependencies exist in this Architectural knowledge. Architectural Decision modeling makes these dependencies explicit and serves as a foundation for knowledge management tools. In practice, however, text templates and informal rich pictures rather than models are used to capture the knowledge; a formal definition of model entities and their relations is missing in the current state of the art. In this paper, we propose such a formal definition of Architectural Decision models as directed acyclic graphs with several types of nodes and edges. In our models, Architectural Decision topic groups, issues, alternatives, and outcomes form trees of nodes connected by edges expressing containment and refinement, decomposition, and triggers dependencies, as well as logical relations such as (in)compatibility of alternatives. The formalization can be used to verify integrity constraints and to organize the Decision making process; production rules and dependency patterns can be defined. A reusable Architectural Decision model supporting service-oriented architecture design demonstrates how we use these concepts. We also present tool support and give a quantitative evaluation.
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reusable Architectural Decision models for enterprise application development
Quality of Software Architectures, 2007Co-Authors: Olaf Zimmermann, Thomas Gschwind, Frank Leymann, Jochen M Kuster, Nelly SchusterAbstract:In enterprise application development and other software construction projects, a critical success factor is to make sound Architectural Decisions. Text templates and tool support for capturing Architectural Decisions exist, but have failed to reach broad adoption so far. One of the inhibitors we perceived on large-scale industry projects is that Architectural Decision capturing is regarded as a retrospective and therefore unwelcome documentation task which does not provide any benefit during the original design work. A major problem of such a retrospective approach is that the Decision rationale is not available to Decision makers when they identify, make, and enforce Decisions. Often a large, possibly distributed, community of Decision makers is involved in these three steps. In this paper, we propose a new conceptual framework for proactive Decision identification, Decision maker collaboration, and Decision enforcement. Based on a meta model capturing reuse and collaboration aspects explicitly, our framework instantiates Decision models from requirements models and reusable Decision templates. These templates capture knowledge gained on other projects employing the same Architectural style. As an exemplary application of these concepts to service-oriented architecture shows, reusable Architectural Decision models can speed up the Decision identification and improve the quality of the Decision making. Reusable Architectural Decision models can also simplify the exchange of architecture design rationale within and between project teams, and expose Decision outcome as model transformation parameters in model-driven software development.
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QoSA - Reusable Architectural Decision models for enterprise application development
Lecture Notes in Computer Science, 2007Co-Authors: Olaf Zimmermann, Thomas Gschwind, Frank Leymann, Jochen M Kuster, Nelly SchusterAbstract:In enterprise application development and other software construction projects, a critical success factor is to make sound Architectural Decisions. Text templates and tool support for capturing Architectural Decisions exist, but have failed to reach broad adoption so far. One of the inhibitors we perceived on large-scale industry projects is that Architectural Decision capturing is regarded as a retrospective and therefore unwelcome documentation task which does not provide any benefit during the original design work. A major problem of such a retrospective approach is that the Decision rationale is not available to Decision makers when they identify, make, and enforce Decisions. Often a large, possibly distributed, community of Decision makers is involved in these three steps. In this paper, we propose a new conceptual framework for proactive Decision identification, Decision maker collaboration, and Decision enforcement. Based on a meta model capturing reuse and collaboration aspects explicitly, our framework instantiates Decision models from requirements models and reusable Decision templates. These templates capture knowledge gained on other projects employing the same Architectural style. As an exemplary application of these concepts to service-oriented architecture shows, reusable Architectural Decision models can speed up the Decision identification and improve the quality of the Decision making. Reusable Architectural Decision models can also simplify the exchange of architecture design rationale within and between project teams, and expose Decision outcome as model transformation parameters in model-driven software development.