Network Function Virtualization (NFV) has recently received significant attention as an innovative way of deploying network services. By decoupling network functions from the physical equipment on which they run, NFV has been proposed as passage towards service agility, better time-to-market, and reduced Capital Expenses (CAPEX) and Operating Expenses (OPEX). One of the main selling points of NFV is its promise for better energy efficiency resulting from consolidation of resources as well as their more dynamic utilization. However, there are currently no studies or implementations which attach values to energy savings that can be expected, which could make it hard for Telecommunication Service Providers (TSPs) to make investment decisions. In this paper, we utilize Bell Labs' GWATT tool to estimate the energy savings that could result from the three main NFV use cases Virtualized Evolved Packet Core (VEPC), Virtualized Customer Premises Equipment (VCPE) and Virtualized Radio Access Network (VRAN). We determine that the part of the mobile network with the highest energy utilization prospects is the Evolved Packet Core (EPC) where virtualization of functions leads to a 22 reduction in energy consumption and a 32 enhancement in energy efficiency.
In this paper, our main objective is to explore how Linux Software Routers (SRs) can deploy advanced and flexible paradigms for supporting novel control-plane functionalities and applications. To this end, we investigate and study a new open-source software (SW) framework: the Distributed SW ROuter Project (DROP), which aims to develop and enable a novel cooperative middleware for distributed IP-router control and management. DROP allows logical network nodes to be built through the aggregation of multiple SRs based on the Linux operating system and commodity hardware, which can be devoted to packet forwarding or control operations. In addition to the original ForCES design, DROP aims to extend router distribution and aggregation concepts by moving them to a network-wide scale to enable and support value-added services for next-generation networks.  Future Internet devices and network infrastructures need to be significantly more energy-efficient, scalable, and flexible in order to realize the extremely virtualized and optimized ICT network infrastructures. In this respect, this article presents a recent extension of an open source software framework, the Distributed Router Open Platform (DROP), to enable a novel distributed paradigm for network function virtualization through the integration of software defined network and information technology (IT) platforms, as well as for the control management of flexible IP router platforms. To answer the need for increased energy efficiency of the network function virtualization paradigms, DROP includes sophisticated power management mechanisms, which are exposed by means of the green abstraction layer (GAL), under consideration for standardization in ETSI. Moreover, the DROP architecture has been specifically designed to act as ?glue? among a large number of the most promising and well-known open source software projects, providing network dataor control-plane capabilities.