Multi-level orchestration of cloud services in OrCS

Abstract

Orchestration is a well known topic in old web services literature. Anyway, what Orchestration means for Cloud services is not yet Clear. Services, especially at lower layers of Cloud Architecture, are complex: Scientific literature has focused on the problem of dealing with proper, efficient and even optimal allocation of Resources when deploying and delivering Cloud services. Hence, management of Resources is what is commonly addressed as Orchestration in the Cloud. Anyway, the increasing complexity of Cloud Architecture and the introduction of new paradigms like Internet of Things, introduced the problem of creating Value Added Services by composition, not only of Resources, but of Services too. In this work we describe an architectural solution for Orchestration at all Cloud Layers. The framework we propose (Orchestrator for Complex Services: OrCS) manages composition of services and resources in order to create composite service based on Cloud Design Patterns. It is based on a Workflow language for description of composition and it enables verification of composite services by means of Model Driven Engineering techniques, providing a precious and easy-to-use tool for Cloud Engineering.

Peer Reviewed

Postprint (author's final draft)