SFCaaS: Service function chains as a service in NFV environments

Abstract

With the growing deployment of emergent technologies like software-defined networking, network services are expected to be revolutionized. In this paper, we investigate offering Service Function Chains as a Service (SFCaaS) in NFV environments. We describe the potential business model to offer such a service and then we address the service function chain provisioning and resource allocation problem. As the chain is deployed thanks to virtual machines (i.e., instances) and links, we conduct first a detailed study of the costs of Amazon EC2 instances with respect to their location, size, type and performance. Afterwards, we address the resource allocation problem for service function chains from the SFC provider's perspective. We formulate the problem as an integer linear program aiming at reducing operational costs of the service function chains (i.e., costs of virtual machine instances and links, and synchronization among the instances). To address large-scale instances of the problem, we also propose a new heuristic algorithm to reduce operational costs taking into account the conducted study of the costs of Amazon EC2 instances. We show through extensive simulations that the proposed heuristic significantly reduces operational costs compared to a baseline algorithm inspired by the existing literature.