78 research outputs found

    Consumer side resource accounting in cloud computing

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    PhD ThesisCloud computing services made available to consumers range from providing basic computational resources such as storage and compute power to sophisticated enterprise application services. A common business model is to charge consumers on a pay-per-use basis where they periodically pay for the resources they have consumed. The provider is responsible for measuring and collecting the resource usage data. This approach is termed provider-side accounting. A serious limitation of this approach is that consumers have no choice but to take whatever usage data that is made available by the provider as trustworthy. This thesis investigates whether it is possible to perform consumer-side resource accounting where a consumer independently collects, for a given cloud service, all the data required for calculating billing charges. If this were possible, then consumers will be able to perform reasonableness checks on the resource usage data available from service providers as well as raise alarms when apparent discrepancies are suspected in consumption figures. Two fundamental resources of cloud computing, namely, storage and computing are evaluated. The evaluation exercise reveals that the resource accounting models of popular cloud service providers, such as Amazon, are not entirely suited to consumer-side resource accounting, in that discrepancies between the data collected by the provider and the consumer can occur. The thesis precisely identifies the causes that could lead to such discrepancies and points out how the discrepancies can be resolved. The results from the thesis can be used by service providers to improve their resource accounting models. In particular, the thesis shows how an accounting model can be made strongly consumer–centric so that all the data that the model requires for calculating billing charges can be collected independently by the consumer. Strongly consumer–centric accounting models have the desirable property of openness and transparency, since service users are in a position to verify the charges billed to them.Cultural Affairs Department, Libyan Embassy, Londo

    Cloud Services Brokerage for Mobile Ubiquitous Computing

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    Recently, companies are adopting Mobile Cloud Computing (MCC) to efficiently deliver enterprise services to users (or consumers) on their personalized devices. MCC is the facilitation of mobile devices (e.g., smartphones, tablets, notebooks, and smart watches) to access virtualized services such as software applications, servers, storage, and network services over the Internet. With the advancement and diversity of the mobile landscape, there has been a growing trend in consumer attitude where a single user owns multiple mobile devices. This paradigm of supporting a single user or consumer to access multiple services from n-devices is referred to as the Ubiquitous Cloud Computing (UCC) or the Personal Cloud Computing. In the UCC era, consumers expect to have application and data consistency across their multiple devices and in real time. However, this expectation can be hindered by the intermittent loss of connectivity in wireless networks, user mobility, and peak load demands. Hence, this dissertation presents an architectural framework called, Cloud Services Brokerage for Mobile Ubiquitous Cloud Computing (CSB-UCC), which ensures soft real-time and reliable services consumption on multiple devices of users. The CSB-UCC acts as an application middleware broker that connects the n-devices of users to the multi-cloud services. The designed system determines the multi-cloud services based on the user's subscriptions and the n-devices are determined through device registration on the broker. The preliminary evaluations of the designed system shows that the following are achieved: 1) high scalability through the adoption of a distributed architecture of the brokerage service, 2) providing soft real-time application synchronization for consistent user experience through an enhanced mobile-to-cloud proximity-based access technique, 3) reliable error recovery from system failure through transactional services re-assignment to active nodes, and 4) transparent audit trail through access-level and context-centric provenance

    Improving Security in Software-as-a-Service Solutions

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    The essence of cloud computing is about moving workloads from your local IT infrastructure to a data center that scales and provides resources at a moments notice. Using a pay-as-you-go model to rent virtual infrastructure is also known as a Infrastructure-as-a-Service (IaaS) offering. This helps consumers provision hardware on-demand without the need for physical infrastructure and the challenges and costs that come with it. When moving to the cloud, however, issues regarding the confidentiality, integrity, and availability of the data and infrastructure arise, and new security challenges compared to traditional on-premises computing appear. It is important for the consumer to know exactly what is their responsibility when it comes to securing software running on IaaS platforms. Axis has one such software solution, henceforth referred to as the 'Axis-hosted cloud service'. There is a need for Axis to improve the client-cloud communication, and in this report, we detail a prototype solution for a new secure communication between client and cloud. Additionally, an evaluation of the prototype is presented. The evaluation is based on a model constructed by studying literature from state-of-the-art cloud service providers and organizations dedicated to defining best practices and critical areas of focus for cloud computing. This was collected and compiled in order to present a summary of the most important aspects to keep in mind when deploying software on an IaaS. It showed that the cloud service fulfills many industry best-practices, such as encrypting data in transit between client and cloud, using virtual private clouds to separate infrastructure credentials from unauthorized access, and following the guidelines from their infrastructure provider. It also showed areas where there was a need for improvement in order to reach a state-of-the-art level. The model proved to be a useful tool to ensure that security best practices are being met by an organization moving to the cloud, and specifically for Axis, the prototype communication solution can be used as a base for further development

    Migration of an On-Premise Single-Tenant Enterprise Application to the Azure Cloud: The Multi-Tenancy Case Study

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    Kokkuvõte Pilvearvutuse edu muudab radikaalselt tavasid kuidas edaspidi infotehnoloogia teenuseid arendatakse, juurutatakse ja hallatakse. Sellest tulenevalt on sõnakõlks „pilve migratsioon“ vägagi aktuaalne paljudes ettevõtetes. Tänu sellele tehnoloogiale on paljud suured ja väikesed ettevõtted huvitatud enda tarkvara, andmebaasi süsteemide ja infrastruktuuri üleviimisest pilve keskkonda. Olemasolevate süsteemide migreerimine pilve võib vähendada kulutusi, mis on seotud vajamineva riistvara, tarkvara paigaldamise ning litsentseerimisega ja samuti selle kõige haldamiseks vajaminevate inimeste palkamisega. Rakenduse ja selle andmete hoidmine pilves, mis teenindab mitmeid üürnike (ik. tenants) võib osutuda kalliks kui ei kasutada jagatud lähenemist üürnike vahel. Sellest tulenevalt on teadlikult disainitud rakenduse ning andme arhitektuur äärmiselt oluline organisatsioonile, mis kasutab mitme-üürniku (ik. multi-tenant) lähenemist. Käesolevas magistritöös kirjeldatakse juhtumiuuringut (ik. case study) ning saadud kogemusi eraldiseiseva majasiseselt paigaldatava rakenduse migreerimisel Azure pilve keskkonda. Töö kirjeldab juristidele mõeldud tootlikkuse mõõtmise tarkvara andmekihi migreerimist Azure pilvekeskkonda. Majasisese ühe tarbijaga tarkvara andmekihi üleviimine efektiivsele mitme-üürniku andmekandja süsteemi pilve keskkonnas nõuab lisaks ka kõrgetasemelise autentimis-mehhanismi disainimist ning realiseerimist. Töö põhirõhk on turvalise skaleeruva ning mitme-üürniku efektiivse andmekandja süsteemi arhitektuuri disainimine ning realiseerimine pilve-keskkonda. Projektis kasutatakse SQL Database’i (endine SQL Azure) poolt pakutavat sisse ehitatud võimekust (SQL Federations) selleks, et tagada turvaline andmete eraldatus erinevate üürnike vahel ja andmebaasi skaleeruvus. Tarkvara andmekihi migreerimine pilve keskkonda toob kaasa kulude vähenemis, mis on seotud tarkvara tarnimisega, paigaldamise ning haldamisega. Lisaks aitab see ettevõttel laieneda uutele turgudele, mis enne migreerimist oli takistatud kohapeal teostava tarkvara paigaldamisega. Tänu pilves olevale andmekihile nõuab uuele kliendile süsteemi paigaldamine väga väikest kulutust.The success of cloud computing is changing the way how information technology services are developed, deployed, maintained and scaled. This makes the ‘migration to the cloud’ a buzzword in the industry for most of the enterprises today. Observing so many advantages of this phenomenon technology, enterprises from small to large scales are interested in migrating their software applications, database systems or infrastructures to cloud scale solutions. Migrating existing systems to a cloud scale solution can reduce the expenses related to costs of the necessary hardware for servers, installation of the operating system environment, license costs of the operating system and database products, deployment of the database products and hiring professional staff for keeping the system up and running. However, storing the application data to a back-end that serves multiple tenants on the cloud will be also costly if the resources on the cloud platform are not shared fairly among tenants. Thus, a carefully designed multi-tenant architecture is essential for an organization that serves multiple tenants. In this master thesis, we will describe a case study and lessons learned on the migration of an enterprise application from an on-premise deployment backend to the Azure Cloud. More specifically, the thesis describes the migration of a productivity tool specialized for legal professionals to a multi-tenant data storage back-ends on Azure Cloud. Moving an on-premise, single-tenant software backend to a multi-tenant data storage system on the cloud will also require design and implementation of authentication mechanisms. The core focus of the work consists of the design and implementation of a secure, scalable and multi-tenant efficient data storage system and application architecture on the cloud. SQL Database (formerly SQL Azure) offers native features (SQL Federations) for the secure isolation of the data among tenants and database scalability which has been used inside the project. Furthermore, the basic application authentication mechanism is enhanced with identity providers such as Google Account and Windows Live ID by embedding native functionality of Windows Azure called Azure Access Control Service to the login mechanism. Migration of the software backend to a cloud scale solution is expected to reduce the costs related to delivery, deployment, maintenance and operation of the software for the business. Furthermore, it will help the business to target new markets since it is a cloud based solution and requires very little initial effort to deliver the software to the new customers

    Seamless Interactions Between Humans and Mobility Systems

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    As mobility systems, including vehicles and roadside infrastructure, enter a period of rapid and profound change, it is important to enhance interactions between people and mobility systems. Seamless human—mobility system interactions can promote widespread deployment of engaging applications, which are crucial for driving safety and efficiency. The ever-increasing penetration rate of ubiquitous computing devices, such as smartphones and wearable devices, can facilitate realization of this goal. Although researchers and developers have attempted to adapt ubiquitous sensors for mobility applications (e.g., navigation apps), these solutions often suffer from limited usability and can be risk-prone. The root causes of these limitations include the low sensing modality and limited computational power available in ubiquitous computing devices. We address these challenges by developing and demonstrating that novel sensing techniques and machine learning can be applied to extract essential, safety-critical information from drivers natural driving behavior, even actions as subtle as steering maneuvers (e.g., left-/righthand turns and lane changes). We first show how ubiquitous sensors can be used to detect steering maneuvers regardless of disturbances to sensing devices. Next, by focusing on turning maneuvers, we characterize drivers driving patterns using a quantifiable metric. Then, we demonstrate how microscopic analyses of crowdsourced ubiquitous sensory data can be used to infer critical macroscopic contextual information, such as risks present at road intersections. Finally, we use ubiquitous sensors to profile a driver’s behavioral patterns on a large scale; such sensors are found to be essential to the analysis and improvement of drivers driving behavior.PHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163127/1/chendy_1.pd

    Desarrollo de servicios de IoT seguros: una revisión de las plataformas de IoT orientada a la seguridad

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    Undoubtedly, the adoption of the Internet of Things (IoT) paradigm has impacted on our every-day life, surrounding us with smart objects. Thus, the potentialities of this new market attracted the industry, so that many enterprises developed their own IoT platforms aiming at helping IoT services’ developers. In the multitude of possible platforms, selecting the most suitable to implement a specific service is not straightforward, especially from a security perspective. This paper analyzes some of the most prominent proposals in the IoT platforms market-place, performing an in-depth security comparison using five common criteria. These criteria are detailed in sub-criteria, so that they can be used as a baseline for the development of a secure IoT service. Leveraging the knowledge gathered from our in-depth study, both researchers and developers may select the IoT platform which best fits their needs. Additionally, an IoT service for monitoring commercial flights is implemented in two previously analyzed IoT platforms, giving an adequate detail level to represent a solid guideline for future IoT developer

    Web services approach for ambient assisted living in mobile environments

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    Web services appeared as a promising technology for Web environments independent of technologies, services, and applications. First, a performance comparison study between the two most used Web service architectures, SOAP and REST, is presented, considering messages exchange between clients and a server. Based on this study, the REST architecture was chosen to deploy the system because it gets better results compared to SOAP architecture. Currently, there are some issues related with this approach that should be studied. For instance, if massive quantities of data are sent to databases it can influence significantly the performance of the whole system. The Advanced Message Queuing Protocol (AMPQ) appears as a promising solution to address this problem. Then, in order to evaluate the performance of this approach, this work presents a performance evaluation and a comparison study of RESTful Web services and the AMQP Protocol considering exchanging messages between clients and a server. The study is based on the averaged exchanged messages for a certain period of time. It was observed and concluded that, for large quantities of messages exchange, the best results comes from the Advanced Message Queuing Protocol. Message Queuing Telemetry Transport (MQTT) was addressed in this work because it is a similar protocol to AMQP but it can be used by mobile devices with a processing capacity smallest unlike the AMQP that needs greater processing capacity. These studies are performed in the context of Ambient Assisted Living environments, since the work was applied to this topic in order to experiment the effectiveness and evaluate the performance of these protocols in this scenario

    A role and attribute based encryption approach to privacy and security in cloud based health services

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    Cloud computing is a rapidly emerging computing paradigm which replaces static and expensive data centers, network and software infrastructure with dynamically scalable “cloud based” services offered by third party providers on an on-demand basis. However, with the potential for seemingly limitless scalability and reduced infrastructure costs comes new issues regarding security and privacy as processing and storage tasks are delegated to potentially untrustworthy cloud providers. For the eHealth industry this loss of control makes adopting the cloud problematic when compliance with privacy laws (such HIPAA, PIPEDA and PHIPA) is required and limits third party access to patient records. This thesis presents a RBAC enabled solution to cloud privacy and security issues resulting from this loss of control to a potentially untrustworthy third party cloud provider, which remains both scalable and distributed. This is accomplished through four major components presented, implemented and evaluated within this thesis; the DOSGi based Health Cloud eXchange (HCX) architecture for managing and exchanging EHRs between authorized users, the Role Based Access Control as a Service (RBACaaS) model and web service providing RBAC policy enforcement and services to cloud applications, the Role Based Single Sign On (RBSSO) protocol, and the Distributed Multi-Authority Ciphertext-Policy Shared Attribute-Based Encryption (DMACPSABE) scheme for limiting access to sensitive records dependent on attributes (or roles) assigned to users. We show that when these components are combined the resulting system is both scalable (scaling at least linearly with users, request, records and attributes), secure and provides a level of protection from the cloud provider which preserves the privacy of user’s records from any third party. Additionally, potential use cases are presented for each component as well as the overall system

    Investigation into a best practice model for providing an integrated user experience with mobile cloud applications

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    Mobile Cloud Computing promises to overcome the physical limitations of mobile devices by executing demanding mobile applications on cloud infrastructure. In practice, implementing this paradigm is difficult; network disconnection often occurs, bandwidth may be limited, and a large power draw is required from the battery, resulting in a poor user experience. This thesis presents a mobile cloud middleware solution, Context Aware Mobile Cloud Services (CAMCS), which provides cloudbased services to mobile devices, in a disconnected fashion. An integrated user experience is delivered by designing for anticipated network disconnection, and low data transfer requirements. CAMCS achieves this by means of the Cloud Personal Assistant (CPA); each user of CAMCS is assigned their own CPA, which can complete user-assigned tasks, received as descriptions from the mobile device, by using existing cloud services. Service execution is personalised to the user's situation with contextual data, and task execution results are stored with the CPA until the user can connect with his/her mobile device to obtain the results. Requirements for an integrated user experience are outlined, along with the design and implementation of CAMCS. The operation of CAMCS and CPAs with cloud-based services is presented, specifically in terms of service description, discovery, and task execution. The use of contextual awareness to personalise service discovery and service consumption to the user's situation is also presented. Resource management by CAMCS is also studied, and compared with existing solutions. Additional application models that can be provided by CAMCS are also presented. Evaluation is performed with CAMCS deployed on the Amazon EC2 cloud. The resource usage of the CAMCS Client, running on Android-based mobile devices, is also evaluated. A user study with volunteers using CAMCS on their own mobile devices is also presented. Results show that CAMCS meets the requirements outlined for an integrated user experience
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