Replication and Caching Systems for the support of VMs stored in File Systems with Snapshots

Recently, in a relatively short timeframe, there were fundamental changes in the way computing power is used. Virtualisation technology has changed both the model of a data centre’s infrastructure and the way physical computers are now managed. This shift is a consequence of today’s fast deployment rate of Virtual Machines (VM) in a high consolidation environment with minimal need for human management. New approaches to virtualisation techniques are being developed at a surprisingly fast rate, leading to a new exciting and vibrating ecosystem of platforms and services. We see the big industry players tackling problems such as Desktop Virtualisation with moderate success, but completely ignoring the computation power already present in their clients’ infrastructures and, instead, opting for a costly solution based on powerful new machines. There’s still room for improvement in Virtual Desktop Infrastructure (VDI) and development of new architectures that take advantage of the computation power available at the user’s desk, with a minimum effort on the management side; Infrastructure for Client-Based Desktops (iCBD) is one of these projects. This thesis focuses on the development of mechanisms for the replication and caching of VM images stored in a local filesystem, albeit one with the ability to perform snapshots. In this work, there are some challenges to address: the proposed architecture must be entirely distributed and completely integrated with the already existing client-based VDI platform; and it must be able to efficiently cope with very large, read-only files, (some of them snapshots) and handle their multiple versions. This work will also explore the challenges and advantages of deploying such a system in a high throughput network, with both high availability and scalability while efficiently supporting a large number of users (and their workstations)

An investigation of smartphone applications: Exploring usability aspects related to wireless personal area networks, context-awareness, and remote information access

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.In this thesis we look into usability in the context of smartphone applications. We selected three research areas to investigate, namely Wireless Personal Area Networks, Context-awareness, and Remote Information Access. These areas are investigated through a series of experiments, which focuses on important aspects of usability within software applications. Additionally, we mainly use smartphone devices in the experiments. In experiment 1, Multi-Platform Bluetooth Remote Control, we investigated Wireless Personal Area Networks. Specifically, we implemented a system consisting of two clients, which were created for Java ME and Windows Mobile, and integrated with a server application installed on a Bluetooth-enabled laptop. For experiments 2 and 3, Context-aware Meeting Room and PainDroid: an Android Application for Pain Management, we looked closely at the research area of Contextawareness. The Context-aware Meeting Room was created to automatically send meeting participants useful meeting notes during presentations. In experiment 3, we investigated the use of on-device sensors for the Android platform, providing an additional input mechanism for a pain management application, where the accelerometer and magnetometer were used. Finally, the last research area we investigated was Remote Information Access, where we conducted experiment 4, Customised Android Home Screen. We created a system that integrated both a cloud-based server application and a mobile client running on the Android platform. We used the cloud-computing platform to provide context management features, such as the ability to store the user configuration that was automatically pushed to the mobile devices

A Software Architecture for Adaptive Modular Sensing Systems

In this thesis, a novel software architecture and knowledge representation scheme is described that facilitates the combination and reconfiguration of modular sensor and actuator components, termed transducer interface modules (TIMs), to produce flexible modular sensor systems. Each TIM provides a core sensing or actuation functionality. A composite sensor is able to automatically determine its overall geometry and assume an appropriate collective identity, and if reconfigured, may then assume a different identity to match its new geometry. In current practice, a fixed combination of sensors and actuators is typically utilized, and is tailored to a specific application. Such systems cannot be cheaply or quickly reconfigured to handle a change in process requirements. Domains that may benefit from easily reconfigurable modular sensing systems include flexible inspection, mobile robotics, surveillance, and even space exploration. The software architecture is distributed, and is comprised of six layers where the implementation of each layer is encapsulated from the layer above, to which it provides service. The use of a distributed and layered architecture promotes scalability, mitigates against a single point of failure, and enables each layer to be easily implemented, modified, and debugged independently of the others. The modularization of the software architecture is further facilitated through the utilization of a pre-emptive real-time operating system, which enables the concurrent execution of the various software components specific to the architecture that implement the services provided within most of its layers. Among the layers comprising the software architecture is a virtual machine layer, which implements a lightweight, architecture-specific version of Sun Microsystems’ Java Virtual Machine that runs on top of the real-time operating system. The integration of a virtual machine enables the platform-independent template algorithms utilized at the composition layer to be written once and executed on any TIM irrespective of its underlying hardware architecture. These template algorithms are unique to this software architecture and provide intelligence to a set of heterogeneous TIMs, enabling them to collaborate and behave as a single entity termed a logical module. The evaluation of the software architecture consists of performing multiple runs of two tests in which select sensors and actuators are associated with TIMs that are then allowed to interact in order to form a logical entity. The first test evaluates the behaviour of a logical module in which the constituent TIMs interact entirely through wireless communication. The second test evaluates the behaviour of a logical module in which the constituent TIMs are physically connected in various orientations, and interact through both wireless communication as well as through their physically connected faces. In both tests, correct behaviour was exhibited. However, the performance and scalability of the architecture was somewhat restricted by the limited processing and memory resources present in the current implementation of the TIMs. The design of the software architecture facilitates easy portability between embedded platforms and scales with increasing hardware capability. Therefore, utilization of future TIM hardware variations possessing increased processing and memory resources will reduce the latencies introduced throughout the architecture and lead to tangible improvements in its performance

Mobiilien liiketoimintaekosysteemien menestystekijät: laitteistokeskeisistä liiketoimintamalleista sisältöön ja mainontaan

For firms operating in a networked economy or business ecosystems, value creation may be highly dependent on the relationships with other firms, which has added a significant amount of complexity particularly to strategic and product-related decision-making. In systems thinking, a firm is seen as part of a wider economic ecosystem and environment where it influences and is influenced by other firms. Within a business ecosystem, firms coevolve capabilities around innovations, working both cooperatively and competitively to support new products, satisfy customers, and incorporate the following round of innovations. Ecosystems are often formed around platforms on which products and complements are built, and platforms may also facilitate transactions between distinct groups of users in a two or multi-sided market. In this study, established theoretical concepts have been brought together to analyze the success factors of mobile business ecosystems in a holistic manner. Additionally, the impact of the historical legacy and path-dependent evolution of a firm’s previous business activities, capabilities, and assets on decisions the firm has made in its ecosystem and platform strategies is studied, and a novel theoretical concept, ‘angle of entry’, is recognized. Through a qualitative multiple case study of three leading companies in the smartphone business and their respective business ecosystems, eight common success factors are identified that have contributed to the disruption of the smartphone business by these three new entrants from the IT world, replacing the incumbents. Based on the results, it can be stated that all three leading ecosystems utilize, at least to a certain extent, closed source code to protect their differentiating or otherwise significantly value-adding software components. Similarly, the product platforms of all three ecosystems offer sufficiently open application programming interfaces so that device manufacturers, accessory makers, and developers are able to create products and apps with meaningful differentiation.Verkostoituneessa taloudessa tai liiketoimintaekosysteemeissä toimivien yritysten arvonluonti saattaa olla hyvinkin riippuvaista suhteista muihin yrityksiin, mikä on lisännyt erityisesti strategisen ja tuotteisiin liittyvän päätöksenteon kompleksisuutta huomattavasti. Järjestelmäajattelussa yritys nähdään osana laajempaa taloudellista ekosysteemiä ja ympäristöä, jossa se vaikuttaa muihin yrityksiin ja on samalla ympäristönsä vaikutuksen kohteena. Liiketoimintaekosysteemissä yritykset kehittävät yhdessä kyvykkyyksiään innovaatioiden ympärillä tehden yhteistyötä ja kilpaillen samalla tukeakseen uusia tuotteita, tyydyttääkseen asiakkaita ja ottaakseen käyttöön uusia innovaatioita. Ekosysteemeitä muodostuu usein tuotealustojen ympärille, ja lisäksi alustat voivat välittää transaktioita erillisten käyttäjäryhmien välillä nk. kaksi- tai useampipuolisessa markkinassa. Tässä tutkimuksessa on yhdistetty tunnettuja teoreettisia käsitteitä mobiilialan liiketoimintaekosysteemien menestystekijöiden analysoimiseksi kokonaisvaltaisesti. Lisäksi on tutkittu yrityksen historian ja sen toimintojen, kyvykkyyksien ja resurssien polkuriippuvaisen evoluution vaikutuksia sen päätöksiin ekosysteemi- ja tuotealustastrategioissa. Tämän tuloksena on tunnistettu uusi teoriakäsite, ‘tulokulma’. Kolmesta johtavasta älypuhelinliiketoiminnan yrityksestä ja näiden kunkin ekosysteemistä tehdyn kvalitatiivisen monitapaustutkimuksen perusteella työssä tunnistetaan kahdeksan yhteistä menestystekijää, jotka ovat auttaneet näitä IT-maailmasta tulleita tulokasyrityksiä mullistamaan älypuhelinliiketoiminnan syrjäyttäen alan vanhat johtoyritykset. Tulosten perusteella voidaan todeta, että kaikki kolme johtavaa ekosysteemiä hyödyntävät ainakin jossain määrin suljettua lähdekoodia suojatakseen erilaistamista tai muuten merkittävää lisäarvoa tuottavia ohjelmistokomponenttejaan. Samoin kaikkien kolmen ekosysteemin tuotealustat tarjoavat riittävästi avoimia sovellusrajapintoja, jotta laitevalmistajat ja sovelluskehittäjät pystyvät luomaan tarpeeksi erilaistettuja tuotteita ja sovelluksia

Development of virtual network computing (VNC) environment for networking and enhancing user experience

Virtual Network Computing (VNC) is a thin client developed by Real VNC Ltd, Formerly of Olivetti Research Ltd/AT&T labs Cambridge and can be used as a collaborative environment, therefore it has been chosen as the basis of this research study. The purpose of this thesis is to investigate and develop a VNC based environment over the network and to improve the users’ Quality of Experience (QoE) of using VNC between networked groups by the incorporation of videoconferencing with VNC and enhancing QoE in Mobile environments where the network status is far from ideal and is prone to disconnection. This thesis investigates the operation of VNC in different environments and scenarios such as wireless environments by investigating user and device mobility and ways to sustain their seamless connection when in motion. As part of the study I also researched all groups that implement VNC like universities, research groups and laboratories and virtual laboratories. In addition to that I identified the successful features and security measures in VNC in order to create a secure environment. This was achieved by pinpointing the points of strength and weakness in VNC as opposed to popular thin clients and remote control applications and analysing VNC according to conforming to several security measures. Furthermore, it is reasonable to say that the success of any scheme that attempts to deliver desirable levels of Quality of Service (QoS) of an effective application for the future Internet must be based, not only on the progress of technology, but on usersʹ requirements. For instance, a collaborative environment has not yet reached the desired expectation of its users since it is not capable of handling any unexpected events which can result from a sudden disconnection of a nomadic user engaged in an ongoing collaborative session; this is consequently associated with breaking the social dynamics of the group collaborating in the session. Therefore, I have concluded that knowing the social dynamics of application’s users as a group and their requirements and expectations of a successful experience can lead an application designer to exploit technology to autonomously support the initiating and maintaining of social interaction. Moreover, I was able to successfully develop a VNC based environment for networked groups that facilitates the administration of different remote VNC sessions. In addition to a prototype that uses videoconferencing in parallel to VNC to provide a better user’s QoE of VNC. The last part of the thesis was concerned with designing a framework to improve and assess QoE of all users in a collaborative environment where it can be especially applied in the presence of nomadic clients with their much frequent disconnections. I have designed a conceptual algorithm called Improved Collaborative Quality of Experience (IC‐QoE), an algorithm that aims to eliminate frustration and improve QoE of users in a collaborative session in the case of disconnections and examined its use and benefits in real world scenarios such as research teams and implemented a prototype to present the concepts of this algorithm. Finally, I have designed a framework to suggest ways to evaluate this algorithm

An investigation of smartphone applications : exploring usability aspects related to wireless personal area networks, context-awareness, and remote information access

In this thesis we look into usability in the context of smartphone applications. We selected three research areas to investigate, namely Wireless Personal Area Networks, Context-awareness, and Remote Information Access. These areas are investigated through a series of experiments, which focuses on important aspects of usability within software applications. Additionally, we mainly use smartphone devices in the experiments. In experiment 1, Multi-Platform Bluetooth Remote Control, we investigated Wireless Personal Area Networks. Specifically, we implemented a system consisting of two clients, which were created for Java ME and Windows Mobile, and integrated with a server application installed on a Bluetooth-enabled laptop. For experiments 2 and 3, Context-aware Meeting Room and PainDroid: an Android Application for Pain Management, we looked closely at the research area of Contextawareness. The Context-aware Meeting Room was created to automatically send meeting participants useful meeting notes during presentations. In experiment 3, we investigated the use of on-device sensors for the Android platform, providing an additional input mechanism for a pain management application, where the accelerometer and magnetometer were used. Finally, the last research area we investigated was Remote Information Access, where we conducted experiment 4, Customised Android Home Screen. We created a system that integrated both a cloud-based server application and a mobile client running on the Android platform. We used the cloud-computing platform to provide context management features, such as the ability to store the user configuration that was automatically pushed to the mobile devices.EThOS - Electronic Theses Online ServiceGBUnited Kingdo