Decision Models for Selecting Architecture Patterns and Strategies in Quantum Software Systems
Mst Shamima Aktar, Peng Liang, Muhammad Waseem, Amjed Tahir, Mojtaba Shahin, Muhammad Azeem Akbar, Arif Ali Khan, Aakash Ahmad, Musengamana Jean de Dieu, Ruiyin Li
Quantum software is an emerging class of software systems, services, and applications that leverage the principles of quantum mechanics through programmable quantum bits (qubits) and quantum gates to perform computations that offer advantages for certain classes of problems. Quantum software architecture enables quantum software developers to abstract away implementation-specific details (i.e., mapping of qubits and quantum gates to high-level architectural components and connectors). Architecture patterns provide proven solutions to recurring design problems, while architecture strategies are approaches that guide the overall design and evolution of a system to meet specific goals. Such patterns and strategies are needed because quantum software systems involve complex hybrid quantum-classical design concerns. However, quantum software practitioners face significant challenges in selecting and implementing appropriate patterns and strategies. To address these challenges, this study proposes decision models for selecting patterns and strategies in six critical design areas in quantum software systems: Communication, Decomposition, Data Processing, Fault Tolerance, Integration and Optimization, and Algorithm Implementation. These decision models are constructed based on data collected from both a mining study (GitHub and Stack Exchange) and an SLR, which were used to identify relevant patterns and strategies with their involved QAs. We then conducted semi-structured interviews with 30 quantum software practitioners to evaluate the familiarity, understandability, completeness, and usefulness of the proposed decision models. The results show that the proposed decision models can aid practitioners in selecting suitable patterns and strategies to address the challenges related to the architecture design of quantum software systems. The dataset is at https://github.com/shamimaaktar1/DMQSA
Quantum software is an emerging class of software systems, services, and applications that leverage the principles of quantum mechanics through programmable quantum bits (qubits) and quantum gates to perform computations that offer advantages for certain classes of problems. Quantum software architecture enables quantum software developers to abstract away implementation-specific details (i.e., mapping of qubits and quantum gates to high-level architectural components and connectors). Architecture patterns provide proven solutions to recurring design problems, while architecture strategies are approaches that guide the overall design and evolution of a system to meet specific goals. Such patterns and strategies are needed because quantum software systems involve complex hybrid quantum-classical design concerns. However, quantum software practitioners face significant challenges in selecting and implementing appropriate patterns and strategies. To address these challenges, this study proposes decision models for selecting patterns and strategies in six critical design areas in quantum software systems: Communication, Decomposition, Data Processing, Fault Tolerance, Integration and Optimization, and Algorithm Implementation. These decision models are constructed based on data collected from both a mining study (GitHub and Stack Exchange) and an SLR, which were used to identify relevant patterns and strategies with their involved QAs. We then conducted semi-structured interviews with 30 quantum software practitioners to evaluate the familiarity, understandability, completeness, and usefulness of the proposed decision models. The results show that the proposed decision models can aid practitioners in selecting suitable patterns and strategies to address the challenges related to the architecture design of quantum software systems. The dataset is at https://github.com/shamimaaktar1/DMQSA
Quantum computing systems rely on the principles of quantum mechanics to perform a multitude of computationally challenging tasks more efficiently than their classical counterparts. The architecture of software-intensive systems can empower architects who can leverage architecture-centric processes, practices, description languages to model, develop, and evolve quantum computing software (quantum software for short) at higher abstraction levels. We conducted a Systematic Literature Review (SLR) to investigate (i) architectural process, (ii) modelling notations, (iii) architecture design patterns, (iv) tool support, and (iv) challenging factors for quantum software architecture. Results of the SLR indicate that quantum software represents a new genre of software-intensive systems; however, existing processes and notations can be tailored to derive the architecting activities and develop modelling languages for quantum software. Quantum bits (Qubits) mapped to Quantum gates (Qugates) can be represented as architectural components and connectors that implement quantum software. Tool-chains can incorporate reusable knowledge and human roles (e.g., quantum domain engineers, quantum code developers) to automate and customise the architectural process. Results of this SLR can facilitate researchers and practitioners to develop new hypotheses to be tested, derive reference architectures, and leverage architecture-centric principles and practices to engineer emerging and next generations of quantum software.
Quantum computing systems rely on the principles of quantum mechanics to perform a multitude of computationally challenging tasks more efficiently than their classical counterparts. The architecture of software-intensive systems can empower architects who can leverage architecture-centric processes, practices, description languages, etc., to model, develop, and evolve quantum computing software (quantum software for short) at higher abstraction levels. We conducted a systematic literature review (SLR) to investigate (i) architectural process, (ii) modeling notations, (iii) architecture design patterns, (iv) tool support, and (iv) challenging factors for quantum software architecture. Results of the SLR indicate that quantum software represents a new genre of software-intensive systems; however, existing processes and notations can be tailored to derive the architecting activities and develop modeling languages for quantum software. Quantum bits (Qubits) mapped to Quantum gates (Qugates) can be represented as architectural components and connectors that implement quantum software. Tool-chains can incorporate reusable knowledge and human roles (e.g., quantum domain engineers, quantum code developers) to automate and customize the architectural process. Results of this SLR can facilitate researchers and practitioners to develop new hypotheses to be tested, derive reference architectures, and leverage architecture-centric principles and practices to engineer emerging and next generations of quantum software.
As quantum computing continues to advance, the development of reliable and scalable quantum software systems becomes increasingly crucial. However, designing and implementing hybrid (quantum-classical) software systems poses unique challenges that require novel approaches and best practices. This position paper argues for the importance of developing architectural and design patterns specific to Quantum Software Engineering (QSE). We provide an overview of existing quantum software design patterns (more focused on low-level, programming details) and highlight the lack of patterns addressing hybrid software systems and architectural patterns. We discuss the key challenges that architectural patterns should address, including quantum-classical integration, maintainability, efficiency, and security. We also discuss the implications for practitioners, providing guidance on how to think high-level about hybrid software development process. Finally, we outline future research directions and emphasize the need for collaboration between the quantum computing and software engineering communities to establish a comprehensive high-level patterns framework for QSE.
Addressing problems beyond classical computing limits is sparking an increasing interest in Quantum Computing. However, despite their adequacy to address specific problems, quantum algorithms cover a limited subset of the functionality required in real-world computing systems. Additionally, they require expensive specialized hardware. To overcome this issue, hybrid (quantum-classical) software systems are emerging as a promising way to integrate both computing paradigms by applying the principles of Service-Oriented Architectures (SOA). Still, the design and deployment of hybrid service-based systems faces unique challenges like the idiosyncrasies and constraints of NISQ computers (e.g., algorithms that can only run in specific machines, disparate quality attribute metrics), and the management of structural and behavioural properties of service-based applications. From the SOA perspective, architectural decisions need to be made by performing a trade-off analysis and providing quantitative guarantees of system configurations under prescribed levels of uncertainty. In this paper, a method to explore the design space of quantum-classical applications is provided by a formalization of an architectural style of hybrid applications. The obtained results demonstrate that the proposed method successfully identifies decision boundaries. It enables the dynamic selection of the most suitable hybrid or classical configuration based on the user's QoS criteria.
Quantum software engineering (QSE) has emerged as a discipline to address the challenges associated with developing software systems in the context of advancing quantum computing technology. This paper explores architectural design patterns specific to QSE. Building on previous work highlighting the need for high-level patterns, we analyze emerging architectural approaches in quantum computing. We identify key challenges unique to hybrid quantum-classical systems and propose a preliminary taxonomy of QSE architectural patterns. These patterns address recurring design problems in areas such as quantum resource management and classical-quantum integration. We describe several potential patterns and discuss their theoretical applications in hybrid software systems. This work aims to provide a foundation for further research into standardizing QSE architectural practices, with the goal of enhancing various quality characteristics of hybrid software (e.g., modularity or maintainability) in the NISQ era and beyond.
Quantum Software Engineering (QSE) is a recent trend - focused on unifying the principles of quantum mechanics and practices of software engineering - to design, develop, validate, and evolve quantum age software systems and applications. Software architecture for quantum computing (a.k. a. quantum software architectures (QSA)) supports the design, development, and maintenance etc. phases of quantum software systems using architectural components and connectors. QSA can enable quantum software designers and developers to map the operations of Qubits to architectural components and connectors for implementing quantum software. This research aims to explore the role of QSAs by investigating (i) architectural process having architecting activities, and (ii) human roles that can exploit available tools to automate and customise architecture-centric implementation of quantum software. Results of this research can facilitate knowledge transfer, enabling researchers and practitioners, to address challenges of architecture-centric implementation of quantum software systems.