In the last few years SDN and NFV have been introduced with the potential to change the ossified Internet paradigm, with the final goal of creating a more agile and flexible network, at the same time reducing both CAPEX and OPEX costs. For this reason, a lot of research efforts have been devoted to optimize the implementation of these technologies, also inheriting experience from data center management. However, orchestration and management of SDN/NFV nodes present new challenges in respect of data center management, mainly due to the telecommunications context where NFV resides. With this in mind, the target of this paper is to define a management model for NFV customers and service providers, a green policy of the Customer Premises Equipment (CPE) nodes, and an analytical model to support their design. The model is then applied to a case study to demonstrate how it can be used to optimize system performance and choose the most important parameters characterizing the design of a CPE node.