Dana Petcu

MODAClouds: a model-driven approach for the design and execution of applications on multiple clouds

Cloud computing is emerging as a major trend in the ICT industry. While most of the attention of the research community is focused on considering the perspective of the Cloud providers, offering mechanisms to support scaling of resources and interoperability and federation between Clouds, the perspective of developers and operators willing to choose the Cloud without being strictly bound to a specific solution is mostly neglected. We argue that Model-Driven Development can be helpful in this context as it would allow developers to design software systems in a cloud-agnostic way and to be supported by model transformation techniques into the process of instantiating the system into specific, possibly, multiple Clouds. The MODAClouds (MOdel-Driven Approach for the design and execution of applications on multiple Clouds) approach we present here is based on these principles and aims at supporting system developers and operators in exploiting multiple Clouds for the same system and in migrating (part of) their systems from Cloud to Cloud as needed. MODAClouds offers a quality-driven design, development and operation method and features a Decision Support System to enable risk analysis for the selection of Cloud providers and for the evaluation of the Cloud adoption impact on internal business processes. Furthermore, MODAClouds offers a run-time environment for observing the system under execution and for enabling a feedback loop with the design environment. This allows system developers to react to performance fluctuations and to re-deploy applications on different Clouds on the long term.

Portable Cloud applications-From theory to practice

The adoption of the Cloud computing concept and its market development are nowadays hindered by the problem of application, data and service portability between Clouds. Open application programming interfaces, standards and protocols, as well as their early integration in the software stack of the new technological offers, are the key elements towards a widely accepted solution and the basic requirements for the further development of Cloud applications. An approach for a new set of APIs for Cloud application development is discussed in this paper from the point of view of portability. The first available, proof-of-the-concept, prototype implementation of the proposed API is integrated in a new open-source deployable Cloudware, namely mOSAIC, designed to deal with multiple Cloud usage scenarios and providing further solutions for portability beyond the API.

Building a mosaic of clouds

The current diversity of Cloud computing services, benefic for the fast development of a new IT market, hinders the easy development, portability and inter-operability of Cloud oriented applications. Developing an application oriented view of Cloud services instead the current provider ones can lead to a step forward in the adoption of Cloud computing on a larger scale than the actual one. In this context, we present a position paper exposing the concepts behind a recent proposal for an open-source application programming interface and platform for dealing with multiple Cloud computing offers.

Portability and interoperability between clouds: challenges and case study

The greatest challenge beyond trust and security for the long-term adoption of cloud computing is the interoperability between clouds. In the context of world-wide tremendous activities against the vendor lock-in and lack of integration of cloud computing services, keeping track of the new concepts and approaches is also a challenge. We considered useful to provide in this paper a snapshot of these concepts and approaches followed by a proposal of their classification. A new approach in providing cloud portability is also revealed.

Multi-Cloud: expectations and current approaches

Using resources and services from multiple Clouds is a natural evolution from consuming the ones from in-silo Clouds. Technological and administrative barriers are however slowing the process. Fortunately the recent years are marked by the appearance of several solutions that are partially overpassing them. However, the approaches are quite various and not adopted at large scale. This paper intends to offer a snapshot of the current state-of-the-art and to identify the future steps in building Multi-Clouds. A list of basic requirements for a Multi-Cloud is proposed.

Experiences in building a mOSAIC of clouds

The diversity of Cloud computing services is challenging the application developers as various and non-standard interfaces are provided for these services. Few middleware solutions were developed until now to support the design, deployment and execution of service-independent applications as well as the management of resources from multiple Clouds. This paper focuses on one of these advanced middleware solutions, called mOSAIC. Written after the completion of its development, this paper presents an integrated overview of the mOSAIC approach and the use of its various software prototypes in a Cloud application development process. We are starting from the design concepts and arrive to various applications, as well as to the position versus similar initiatives.

A cloud agency for SLA negotiation and management

Resources management facilities, based on service level agreements, are needed in the Cloud in order to negotiate a collection of inter-connected and virtualized computers between resource providers and consumers. In this paper we present the architectural design of a system named Cloud Agency which aims to respond to this need and to offer added value to the existing Cloud services. This system is in charge to broker the collection of Cloud resources from different providers that fulfills at the best the requirements of users applications. The user is able to delegate to the Agency the necessary checks of the agreement fulfilment, the monitoring of resource utilization and eventually necessary re-negotiations.

Adaptive Pareto Differential Evolution and Its Parallelization

An adaptive Pareto differential evolution algorithm for multi-objective optimization is proposed. Its effectiveness on approximating the Pareto front is compared with that of SPEA [9] and of SPDE [2]. A parallel implementation, based on an island model with a random connection topology, is also analyzed. The parallelization efficiency derives from the simple migration strategy. Numerical tests were performed on a cluster of workstations.

Consuming Resources and Services from Multiple Clouds

The consumption of resources and services from multiple Clouds for reasons like high availability, cost reductions or special features is a natural evolution from in-silo Clouds. Several middleware are already available for multiple Clouds. However, due to the complexity of the technical solutions, their approaches are quite different and a classification is needed to guide the potential users. This paper looks to the reports on multiple Cloud topics and proposes a specific taxonomy. It identifies the ready-to-use software and services and classifies them according the taxonomy. It also underlines the driving needs and requirements from consumers’ and providers’ point of views. A particular Cloudware is provided as an example for the degree of requirements fulfillment.

Building an interoperability API for Sky computing

The federation of Cloud resources can be treated at different levels of abstractions. In this paper we focus on application programming interfaces for building Cloud-based applications using services from multiple Cloud providers. A full stack of APIs is proposed to decouple the development of a Cloud-based application from its deployment and execution. A particular attention is paid to the design of the interoperability API aiming to provide programming language interoperability and protocol syntax or semantic enforcements.