ClouNS - A Cloud-native Application Reference Model for Enterprise Architects

The capability to operate cloud-native applications can generate enormous business growth and value. But enterprise architects should be aware that cloud-native applications are vulnerable to vendor lock-in. We investigated cloud-native application design principles, public cloud service providers, and industrial cloud standards. All results indicate that most cloud service categories seem to foster vendor lock-in situations which might be especially problematic for enterprise architectures. This might sound disillusioning at first. However, we present a reference model for cloud-native applications that relies only on a small subset of well standardized IaaS services. The reference model can be used for codifying cloud technologies. It can guide technology identification, classification, adoption, research and development processes for cloud-native application and for vendor lock-in aware enterprise architecture engineering methodologies

Scalable invoice-based B2B payments with microservices

Paying by invoice has several advantages for businesses over conventional payment methods such as Debit/Credit cards. An invoice not only allows a buyer to make the purchase on credit but also contains the tax information for each purchased item. Businesses need to save this information in their financial records and report it to the authorities. The core challenge in an invoice-based payment method is the ability to make an accurate credit decision for a given purchase. Such a credit decision requires information about the buying company such as their credit rating. The company information is gathered in real time from different third-party sources. In this context, Enterpay Oy provides an invoiced-based B2B payment solution and is growing its payment service to European countries. In order to support this expansion, Enterpay needs to develop new capabilities such as the ability to detect fraudulent purchases. These new features require the application architecture to be flexible in terms of technology. For example, different components of the service should be built with the most suited programming language, libraries, and frameworks. The goal of this thesis is to enable efficient scaling and high availability for Enterpay's payment service. Thus, we have migrated from a monolithic a microservice-based architecture. This transition allows us to choose the best suited technology for the business case of the given microservice. We extracted various modules from the original monolithic application, which have different scalability criteria. We built these modules as Docker containers, which run as independent microservices. We used Kubernetes as the container orchestration framework and deployed the microservice in Amazon Web Services (AWS). Finally, we conducted experiments to measure the performance of the service with the new architecture. We found that this architecture not only scales faster but also recovers from instance failures quicker than the previous solution. Additionally, we noticed that the average response time of service request is similar in both architectures. Finally, we observed that new microservices can be built using different technology stack and deployed conveniently in the same Kubernetes cluster

Revitalizing Legacy Systems: Extracting Key Features for Software Transplantation

The creation of intelligent software depends on the ability to transfer software without any restrictions. In this article, a crucial stage in software engineering, the feature extraction for effective software transplantation, is discussed. As hardware, operating systems, or other factors change, it is commonly necessary to move software from one environment to another. It is vital to identify and extract the relevant software characteristics, which might be challenging given how complex software is, in order to carry out efficient software transplantation. On the other hand, the procedure to extract these attributes from the software might be time-consuming and need extensive understanding. To address this, we propose a transplantation strategy that prioritizes automation with the help of AWS. Our approach involves an agent running on the application server (on-premises). It performs the task of feature identification, extraction and deployment on AWS Cloud. Currently, our strategy is confined to Java and .NET applications