Cross-layer resource orchestration for cloud service delivery: A seamless SDN approach

Abstract One of the main challenges of cloud-based service provisioning is to deploy a coordinated control of both application- and network-layer resources in order to provide adaptive service data delivery and adequate user service experiences. In this work we propose a signaling framework architecture for cross-layer resource orchestration, where service awareness provided by session control is effectively combined with the flexibility of software-defined network control. Following a hands-on approach, the proposed solution takes advantage of existing and commonly deployed technologies aiming at an incremental deployment of the software-defined control mechanisms for the purpose of cross-functional service orchestration. The signaling framework is presented and validated through experimental activities carried out on a test-bed reproducing a realistic cloud-based service scenario. Results are compared against an analytical model that allows to investigate and quantify the sensitivity of the cloud-based service performance to the most relevant system parameters. The study demonstrates that a critical role is played by the limitations of the response time of real devices such as commercial routers, and highlights how orchestration functions can mitigate the effect of such limitations while addressing scalability of the overall system.