Complex user-end procedures for the execution of computationally expensive processes and tools on high performance computing platforms can hinder the scientific progress of researchers across many domains. In addition, such processes occasionally cannot be executed on user-end platforms either due to insufficient hardware resources or unacceptably long computing times. Such circumstances currently extend to highly sophisticated algorithms and tools utilized for analysis of fluorescent imaging data. Although an extensive collection of cloud-computing solutions exist allowing software developers to resolve these issues, such solutions often abstract both developers and integrators from the executing hardware particulars and can inadvertently incentivize non-ideal software design practices. The discussion herein consists of the theoretical design and real-world realization of an efficient architecture to enable direct multi-user parallel remote utilization of such research tools. Said networked scalable real-time architecture is multi-tier, extensible by design to a vast collection of application archetypes, and is not strictly limited to imaging analysis applications. Transport layer interfaces for packetized binary data transmission, asynchronous command issuance mechanisms, compression and decompression algorithm aggregation, and relational database management systems for inter-tier communication intermediation enable a robust, lightweight, and efficient architecture for networking and remotely interfacing with fluorescent imaging analysis processes. / M.S. / Collaboration amongst researchers within various technical domains who rely on information processing and analysis tools can be strengthened through the deployment of scientific computing infrastructure that enables their usage via a web interface. The architecture of such infrastructure is preferably efficient, lightweight, and simple while retaining potential future integration capabilities with additional research tools. This work presents the theoretical design and realization of an architecture for networking fluorescent imaging analysis processes so as to make them remotely usable within internal computer networks and across the world wide web.

A adoção de Software como Serviço (do inglês, Software as a Service ou simplesmente SaaS) está em expansão em todo o mundo, alavancada pelas muitas vantagens que esse modelo de distribuição de software oferece tanto para os provedores desses serviços quanto para seus clientes. Em SaaS, o provedor do serviço também é responsável pelo seu desenvolvimento e execução, o que permite a esses provedores fazerem escolhas sobre a arquitetura de seus sistemas visando diminuir a complexidade e os custos relacionados ao seu desenvolvimento e operação. Nesse contexto, um padrão de arquitetura freqüentemente utilizado é o Multitenant, que torna uma mesma instância do software capaz de servir a múltiplos clientes (tenants) simultaneamente. No entanto, sistemas que utilizam Multitenancy enfrentam uma série de desafios, principalmente no que se refere à flexibilidade em atender os requisitos específicos de cada cliente na customização de processos, de fluxos e regras de negócio, e de interfaces com o usuário. Especificamente no problema de customização de interfaces, embora existam trabalhos na literatura relacionados à customização de interfaces Web, e existam implementações de mercado de mecanismos para possibilitar essas customizações, esses trabalhos e mecanismos ou não são projetados especificamente para sistemas Multitenant ou, quando são, não têm sua arquitetura publicada e seu código fonte disponíveis para serem reutilizados. Assim, esta pesquisa investigou uma alternativa para a customização de interfaces Web no contexto de Software como Serviço Multitenant. Como resultado, foi inicialmente definido e implementado um mecanismo não intrusivo para o desenvolvimento de aplicações Multitenant chamado DORMT (Domain-Based Shared-Database Multitenancy), sobre o qual foi possível construir um mecanismo para a customização de interfaces Web, chamado MHT (Multitenant Hierarchical Themes), baseado no padrão MVC (Model-View-Controller ) e nos conceito de temas e de hierarquias / The adoption of Software as a Service (SaaS) is growing worldwide, driven by the many advantages that this software distribution model offers to both service providers and their clients. In SaaS, the service provider is also responsible for the development and the execution of the software, enabling that choices be made in terms of system architecture in order to reduce the complexity and costs related to its development and operation. However, Multitenant systems face a number of challenges, mainly related to flexibility in meeting specific customer requirements in customizing the system processes, flows, business rules and user interfaces. Specifically on the problem of user interface customization, although there are studies in the literature and products on the market that implement mechanism to allow such customizations, these studies and mechanism are not specific to Multitenant systems or the mechanism architecture and source code is not available to be reused. Thus, this study investigated alternatives for Web interfaces customization in the context of Multitenant Software as a Service. As a result, a non intrusive mechanism, called DORMT (Domain-Based Shared-Database Multitenancy), was defined and implemented to allow the development of Multitenant applications, on top of which a mechanism for Web interfaces customization, called MHT (Multitenant Hierarchical themes), based on the MVC pattern, on the concepts of themes and of hierarchies, was built

A adoção de Software como Serviço (do inglês, Software as a Service ou simplesmente SaaS) está em expansão em todo o mundo, alavancada pelas muitas vantagens que esse modelo de distribuição de software oferece tanto para os provedores desses serviços quanto para seus clientes. Em SaaS, o provedor do serviço também é responsável pelo seu desenvolvimento e execução, o que permite a esses provedores fazerem escolhas sobre a arquitetura de seus sistemas visando diminuir a complexidade e os custos relacionados ao seu desenvolvimento e operação. Nesse contexto, um padrão de arquitetura freqüentemente utilizado é o Multitenant, que torna uma mesma instância do software capaz de servir a múltiplos clientes (tenants) simultaneamente. No entanto, sistemas que utilizam Multitenancy enfrentam uma série de desafios, principalmente no que se refere à flexibilidade em atender os requisitos específicos de cada cliente na customização de processos, de fluxos e regras de negócio, e de interfaces com o usuário. Especificamente no problema de customização de interfaces, embora existam trabalhos na literatura relacionados à customização de interfaces Web, e existam implementações de mercado de mecanismos para possibilitar essas customizações, esses trabalhos e mecanismos ou não são projetados especificamente para sistemas Multitenant ou, quando são, não têm sua arquitetura publicada e seu código fonte disponíveis para serem reutilizados. Assim, esta pesquisa investigou uma alternativa para a customização de interfaces Web no contexto de Software como Serviço Multitenant. Como resultado, foi inicialmente definido e implementado um mecanismo não intrusivo para o desenvolvimento de aplicações Multitenant chamado DORMT (Domain-Based Shared-Database Multitenancy), sobre o qual foi possível construir um mecanismo para a customização de interfaces Web, chamado MHT (Multitenant Hierarchical Themes), baseado no padrão MVC (Model-View-Controller ) e nos conceito de temas e de hierarquias / The adoption of Software as a Service (SaaS) is growing worldwide, driven by the many advantages that this software distribution model offers to both service providers and their clients. In SaaS, the service provider is also responsible for the development and the execution of the software, enabling that choices be made in terms of system architecture in order to reduce the complexity and costs related to its development and operation. However, Multitenant systems face a number of challenges, mainly related to flexibility in meeting specific customer requirements in customizing the system processes, flows, business rules and user interfaces. Specifically on the problem of user interface customization, although there are studies in the literature and products on the market that implement mechanism to allow such customizations, these studies and mechanism are not specific to Multitenant systems or the mechanism architecture and source code is not available to be reused. Thus, this study investigated alternatives for Web interfaces customization in the context of Multitenant Software as a Service. As a result, a non intrusive mechanism, called DORMT (Domain-Based Shared-Database Multitenancy), was defined and implemented to allow the development of Multitenant applications, on top of which a mechanism for Web interfaces customization, called MHT (Multitenant Hierarchical themes), based on the MVC pattern, on the concepts of themes and of hierarchies, was built

Molntjänster är ett område inom IT som har vuxit i betydelse under många år, till stor del då de ger aktörer tillgång till datorresurser som ofta skulle vara för kostsamma att underhålla själva. OpenShift är ett sådant verktyg baserat på orkesteringsverktyget Kubernetes. Dessa tillsammans med många andra bygger på så kallad kluster-arkitektur med nätverk av noder som utför olika uppgifter. En mjukvaruarkitektur kallad multitenancy som bygger på att utnyttja systemresurser optimalt genom att flera kunders applikationer körs isolerat parallellt på samma hårdvara har utvecklats. Den medför dock säkerhetsproblem då läckor mellan applikationer måste förhindras.Denna studie har baserat på diskussioner med kunniga inom OpenShift försökt kartlägga vilka säkerhetsproblemen är och de möjliga metoder som finns för att åtgärda dem. Svaret var att det huvudsakligen handlade om hur så kallade secrets hanteras på bästa sätt och några exempel på verktyg för detta gavs. Studien avslutas med en jämförelse om vilka som fungerar bäst med multitenancy som konstaterade att det är ett område där mer forskning behövs då problem finns med alla. / Cloud services is an area in IT that has grown in importance for many years, mainly as they give players access to computer resources that often would be too costly for them to maintain themselves. OpenShift is one such tool based on the orchestration tool Kubernetes. These together with many others are based on so-called cluster architecture with a network of nodes that perform various tasks. A software architecture called multitenancy that is based on utilizing system resources optimally by running several customers’ applications isolated in parallel on the same hardware has been developed. However, it creates security issues as leaks between applications must be prevented. Based on discussions with experts in OpenShift, this study has tried to identify the security issues and the possible methods available to address them. The answer was mainly related to how so-called secrets are handled in the best way and some examples of tools for this were given. The study ends with a comparison of which work best with multitenancy and found that it is an area where more research is needed as there are problems with all.

Context. Cloud computing is getting more and more interest with every year. It is an approach that allows Internet based applications to work in distributed and virtualized cloud environment. It is characterized by on-demand resources and payper-use pricing. Software-as-a-Service (SaaS) is a software distribution paradigm in cloud computing and represents the highest, software layer in the cloud stack. Since most cloud services providers charge for the resource use it is important to create resource efficient applications. One of the way to achieve that is multi-tenant architecture of SaaS applications. It allows the application for efficient self-managing of the resources Objectives. In this study I investigate the influence of tenant-based resource allocation model on cost-effectiveness of SaaS systems. I try to find out weather that model can decrease the system's actual costs in commercial public cloud environment. Methods. I am implementing two authorial SaaS systems: first tenant-unaware and then using tenant-based resource allocation model. Then they are deployed into Amazon public cloud environment. Tests focused on measuring over- and underutilization are conducted in order to compare cost-effectiveness of the solutions. Public cloud provider's billing service is used as a final cost measure. Results. The tenant-based resource allocation model proved to decrease my system's running costs. It also reduced the system's resources underutilization. Similar research was done, but the model was tested in private cloud. In this work the systems were deployed into commercial public cloud. Conclusions. The tenant-based resource allocation model is one of the method to tackle under-optimal resource utilization. When compared to traditional resource scaling it can reduce the costs of running SaaS systems in cloud environments. The more tenant-oriented the SaaS systems are the more benefits that model can provide.

There has been a substantial growth in the usage of data in the past decade, cloud technologies and big data platforms have gained popularity as they help in processing such data on a large scale. Hopsworks is such a managed plat- form for scale out data science. It is an open-source platform for the develop- ment and operation of Machine Learning models, available on-premise and as a managed platform in the cloud. As most of these platforms provide data sci- ence environments to collate the required libraries to work with, Hopsworks provides users with Anaconda environments.Hopsworks provides multi-tenancy, ensuring a secure model to manage sen- sitive data in the shared platform. Most of the Hopsworks features are built around projects, each project includes an Anaconda environment that provides users with a number of libraries capable of processing data. Each project cre- ation triggers a creation of a base Anaconda environment and each added li- brary updates this environment. For an on-premise application, as data science teams are diverse and work towards building repeatable and scalable models, it becomes increasingly important to manage these environments in a central location locally.The purpose of the thesis is to provide a secure storage for these Anaconda en- vironments. As Hopsworks uses a Kubernetes cluster to serve models, these environments can be containerized and stored on a secure container registry on the Kubernetes Cluster. The provided solution also aims to extend the multi- tenancy feature of Hopsworks onto the hosted local storage. The implemen- tation comprises of two parts; First one, is to host a compatible open source container registry to store the container images on a local Kubernetes cluster with fault tolerance and by avoiding a single point of failure. Second one, is to leverage the multi-tenancy feature in Hopsworks by storing the images on the self sufficient secure registry with project level isolation. / Det har skett en betydande tillväxt i dataanvändningen under det senaste decen- niet, molnteknologier och big data-plattformar har vunnit popularitet eftersom de hjälper till att bearbeta sådan data i stor skala. Hopsworks är en sådan hante- rad plattform för att skala ut datavetenskap. Det är en öppen källkodsplattform för utveckling och drift av Machine Learning-modeller, tillgänglig på plats och som en hanterad plattform i molnet. Eftersom de flesta av dessa plattformar tillhandahåller datavetenskapsmiljöer för att samla in de bibliotek som krävs för att arbeta med, ger Hopsworks användare Anaconda-miljöer.Hopsworks tillhandahåller multi-tenancy, vilket säkerställer en säker modell för att hantera känslig data i den delade plattformen. De flesta av Hopsworks- funktionerna är uppbyggda kring projekt, varje projekt innehåller en Anaconda- miljö som ger användarna ett antal bibliotek som kan bearbeta data. Varje projektskapning utlöser skapandet av en basanacondamiljö och varje tillagt bibliotek uppdaterar denna miljö. För en lokal applikation, eftersom datave- tenskapsteam är olika och arbetar för att bygga repeterbara och skalbara mo- deller, blir det allt viktigare att hantera dessa miljöer på en central plats lokalt. Syftet med avhandlingen är att tillhandahålla en säker lagring för dessa Anaconda- miljöer. Eftersom Hopsworks använder ett Kubernetes-kluster för att betjäna modeller kan dessa miljöer containeriseras och lagras i ett säkert container- register i Kubernetes-klustret. Den medföljande lösningen syftar också till att utvidga Hopsworks-funktionen för flera hyresgäster till det lokala lagrade vär- det. Implementeringen består av två delar; Den första är att vara värd för ett kompatibelt register med öppen källkod för att lagra behållaravbildningarna iett lokalt Kubernetes-kluster med feltolerans och genom att undvika en enda felpunkt. Den andra är att utnyttja multihyresfunktionen i Hopsworks genom att lagra bilderna i det självförsörjande säkra registret med projektnivåisole- ring.

In recent years, software tools used for Global Software Development (GSD) processes (e.g., continuous integration, version control and bug tracking) are increasingly being deployed in the cloud to serve multiple users. Multitenancy is an important architectural property in cloud computing in which a single instance of an application is used to serve multiple users. There are two key challenges of implementing multitenancy: (i) ensuring isolation either between multiple tenants accessing the service or components designed (or integrated) with the service; and (ii) resolving trade-offs between varying degrees of isolation between tenants or components. The aim of this thesis is to investigate how to architect the deployment of cloud-hosted service while guaranteeing the required degree of multitenancy isolation. Existing approaches for architecting the deployment of cloud-hosted services to serve multiple users have paid little attention to evaluating the effect of the varying degrees of multitenancy isolation on the required performance, resource consumption and access privilege of tenants (or components). Approaches for isolating tenants (or components) are usually implemented at lower layers of the cloud stack and often apply to the entire system and not to individual tenants (or components). This thesis adopts a multimethod research strategy to providing a set of novel approaches for addressing these problems. Firstly, a taxonomy of deployment patterns and a general process, CLIP (CLoud-based Identification process for deployment Patterns) was developed for guiding architects in selecting applicable cloud deployment patterns (together with the supporting technologies) using the taxonomy for deploying services to the cloud. Secondly, an approach named COMITRE (COmponent-based approach to Multitenancy Isolation Through request RE-routing) was developed together with supporting algorithms and then applied to three case studies to empirically evaluate the varying degrees of isolation between tenants enabled by multitenancy patterns for three different cloud-hosted GSD processes, namely-continuous integration, version control, and bug tracking. After that, a synthesis of findings from the three case studies was carried out to provide an explanatory framework and new insights about varying degrees of multitenancy isolation. Thirdly, a model-based decision support system together with four variants of a metaheuristic solution was developed for solving the model to provide an optimal solution for deploying components of a cloud-hosted application with guarantees for multitenancy isolation. By creating and applying the taxonomy, it was learnt that most deployment patterns are related and can be implemented by combining with others, for example, in hybrid deployment scenarios to integrate data residing in multiple clouds. It has been argued that the shared component is better for reducing resource consumption while the dedicated component is better in avoiding performance interference. However, as the experimental results show, there are certain GSD processes where that might not necessarily be so, for example, in version control, where additional copies of the files are created in the repository, thus consuming more disk space. Over time, performance begins to degrade as more time is spent searching across many files on the disk. Extensive performance evaluation of the model-based decision support system showed that the optimal solutions obtained had low variability and percent deviation, and were produced with low computational effort when compared to a given target solution.