An orchestrator-based SDN framework with its northbound interface

Abstract

Software Defined Networking (SDN) is deemed to empower next generation network and cloud services in several aspects. The authors argue that its high flexibility can be exploited not only in retrieving services efficiently but also in yielding new ones by introducing programming capabilities on its top. This however requires to structure its northbound interface (NBI) with an abstract application programming interface (API), the definition of which is actually one of the SDN challenges. We propose in this paper a global analysis of the capabilities of the NBI of the SDN articulated to a generic but simple double sided model of service lifecycle. Its analysis determines interesting properties of the NBI leading to precisely identify the associated API. We derive from this service lifecycle a general framework structuring the internal architecture of the SDN in two orchestrators dedicated respectively to the management of services and resources. Our approach which provides a firm foundation for the implementation of the NBI is illustrated with an example.