The rOCCI project - Providing cloud interoperability with OCCI 1.1

Abstract

OCCI (Open Cloud Computing Interface) is an open protocol for management of tasks in the cloud environment focused on integration, portability and interoperability with a high degree of extensibility. It is designed to bridge differences between various cloud platforms and provide common ground for users and developers alike. The rOCCI framework, originally developed by GWDG, later adopted and now maintained by CESNET, was written to simplify implementation of the OCCI 1.1 protocol in Ruby and later provided the base for working client and server components giving OCCI support to multiple cloud platforms while ensuring interoperability with other existing implementations. The initial server-side component provided basic functionality and served as a proof of concept when it was adopted by the EGI Federated Cloud Task and was chosen to act as the designated virtual machine management interface. This led to further funding from the EGI-InSPIRE project, development of a full featured client and a new rOCCI-server suitable for production environment. It has also prompted further proliferation of the OCCI protocol, spawned multiple connector/backend implementations and provided developers with valuable feedback and opportunities to test their own implementations of the OCCI standard. This paper aims to provide basic information about the OCCI protocol, introduce its implementation in rOCCI, describe some of the core functionality provided by the rOCCI client and rOCCI-server along with their impact on interoperability in the cloud environment. It also briefly examines its use in the EGI Federated Cloud Task environment and explores the possibility of further integration with other cloud platforms. All this with interoperability in mind. The paper also describes a carefully chosen subset of problems encountered whilst trying to provide interoperability with multiple cloud platforms through the use of the OCCI protocol, with real-world examples and chosen solutions.