I would like to dedicate this thesis to my beloved parents. Abstract The cloud computing paradigm is changing the design, development, deployment, and provisioning of services and corresponding IT infrastructures. Nowadays, users and companies incrementally rely on on-demand cloud resources to access and deliver services, while IT infrastructures are continuously evolving to address cloud needs and support cloud service delivery. This scenario points to a multi-tenant environment where services
more » ... ment where services are built with strong security and scalability requirements, and cost, performance, security and privacy are key factors enabling cloud adoption. New business opportunities for providers and customers come at the price of growing concerns about how data and processes are managed and operated once deployed in the cloud. This context, where companies externalise the IT services to third parties, makes the trustworthiness of IT partners and services a prerequisite for its success. Trustworthiness can be expressed and guaranteed through contracts that enforce Service Level Agreements (SLAs), and in a more general way by assurance techniques. By the term security assurance, we mean all the techniques able to assess and evaluate a given target to demonstrate that a security property is satisfied and the target behaves as expected. However, traditional assurance solutions rely on static verification techniques and assume continuous availability of a trusted evaluator. Such conditions are not valid anymore in the cloud that instead requires new approaches that match its dynamic, distributed and heterogeneous nature. In this thesis, we describe an assurance technique based on certification, towards the definition of a transparent and trusted cloud, from the bare metal to the application layer. The presented assurance approach follows the traditional certification process and extends it by providing continuous, incremental, adaptive and multi-layer verification. We propose a test-based certification scheme assessing non-functional properties of cloud-based services. The scheme is driven by non-functional requirements defined by the certification authority and by a model of the service under certification. We then define an automatic approach to verification of consistency between requirements and models, which is at the basis of the chain of trust supported by the certification scheme. We also present a continuous certificate life cycle management process including both certificate issuing and its adaptation to address contextual changes, versioning and migration. The proposed certification scheme is however partial if certification of cloud composite services is not supported. Cloud computing paradigm in fact, supports service composition
doi:10.13130/gaudenzi-filippo_phd2019-02-01 fatcat:ed5bzw7stba27jnlan22q2sbu4