Technology market is continuing a rapid growth phase where different resource providers and Cloud Management Frameworks are positioning to provide ad-hoc solutions-as management interfaces, information discovery or billing-trying to differentiate from competitors resulting in incompatibilites between them when addressing more complex scenarios like federated clouds.Therefore, grasping interoperability problems present in current infrastructures by studying how existing and emerging standards could enhance the cloud user experience.In this paper we will review the current open challenges in Infrastructure as a Service cloud interoperability and federation, as well as point to the potential standards that should alleviate these problems. We will describe the main challenges regarding cloud federation and in-teroperability.We will showcase and review the existing and emerging standards that can be use to tackle the gaps in cloud federations.
@cite_29: Cloud computing is a new computing paradigm that allows users with different computing demands to access a shared pool of configurable computing resources (e.g., servers, network, storage, database, applications and services). Many commercial cloud providers have emerged in the past 6-7 years, and each typically provides its own cloud infrastructure, APIs and application description formats to access the cloud resources, as well as support for service level agreements (SLAs). Such vendor lock-in has seriously limited the flexibility that cloud end users would like to process, when it comes to deploy applications over different infrastructures in different geographic locations, or to migrate a service from one provider's cloud to another. To enable seamless sharing of resources from a pool of cloud providers, efforts have emerged recently to facilitate cloud interoperability, i.e., the ability for multiple cloud providers to work together, from both the industry and academia. In this article, we conduct a comprehensive survey on the state-of-the-art efforts, with a focus on interoperability among different IaaS (infrastructure as a service) cloud platforms. We investigate the existing studies on taxonomies and standardization of cloud interoperability, as well as practical cloud technologies from both the cloud provider's and user's perspectives to enable interoperation. We pose issues and challenges to advance the topic area, and hope to pave a way for the forthcoming research.
@cite_1: Virtualization offers several benefits for optimal resource utilization over traditional non-virtualized server farms. With improvements in internetworking technologies and increase in network bandwidth speeds, a new era of computing has been ushered in, that of grids and clouds. With several commercial cloud providers coming up, each with their own APIs, application description formats, and varying support for SLAs, vendor lockin has become a serious issue for end users. This article attempts to describe the problem, issues, possible solutions and challenges in achieving cloud interoperability. These issues will be analyzed in the ambit of the European project Contrail that is trying to adopt open standards with available virtualization solutions to enhance users' trust in the clouds by attempting to prevent vendor lock-ins, supporting and enforcing SLAs together with adequate data protection for sensitive data.
@cite_1 work surveyed the existing standards for the management of cloud computing services and infrastructure within the Contrail project so as to avoid vendor lock-in issues and ensure interoperability. In the same line, @cite_29 performed a quite complete survey regarding Infrastructure as a Service access, management and interoperability, studying OVF, CDMI and OCCI @cite_29 . However, they have not entered into other details and challenges such as accounting or information discovery.