applied sciences Review A Brief History of Cloud Application Architectures Nane Kratzke ID Lübeck University of Applied Sciences, Department of Electrical Engineering and Computer Science, 23562 Lübeck, Germany;
[email protected] Received: 14 July 2018; Accepted: 27 July 2018; Published: 14 August 2018 Featured Application: This paper features system and software engineering use cases for large-scale (business) Cloud-native applications (e.g., Netflix, Twitter, Uber, Google Search). Such Cloud-native applications (CNA) provide web-scalability and independent deployability of their components and enable exponential user growth. Furthermore, migration and architecture transformation use cases of existing tiered and on-premise (business) applications are additionally of interest. Thus, questions of how existing and not cloud-ready applications are migratable into cloud environments are covered as well. Abstract: This paper presents a review of cloud application architectures and its evolution. It reports observations being made during a research project that tackled the problem to transfer cloud applications between different cloud infrastructures. As a side effect, we learned a lot about commonalities and differences from plenty of different cloud applications which might be of value for cloud software engineers and architects. Throughout the research project, we analyzed industrial cloud standards, performed systematic mapping studies of cloud-native application-related research papers, did action research activities in cloud engineering projects, modeled a cloud application reference model, and performed software and domain-specific language engineering activities. Two primary (and sometimes overlooked) trends can be identified. First, cloud computing and its related application architecture evolution can be seen as a steady process to optimize resource utilization in cloud computing.