Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> We have built and deployed OpenRoads [11], a testbed that allows multiple network experiments to be conducted concurrently in a production network. For example, multiple routing protocols, mobility managers and network access controllers can run simultaneously in the same network. In this paper, we describe and discuss our deployment of the testbed at Stanford University. We focus on the challenges we faced deploying in a production network, and the tools we built to overcome these challenges. Our goal is to gain enough experience for other groups to deploy OpenRoads in their campus network. <s> BIB001 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Networks are a shared resource connecting critical IT infrastructure, and the general practice is to always leave them on. Yet, meaningful energy savings can result from improving a network's ability to scale up and down, as traffic demands ebb and flow. We present ElasticTree, a network-wide power1 manager, which dynamically adjusts the set of active network elements -- links and switches--to satisfy changing data center traffic loads. ::: ::: We first compare multiple strategies for finding minimum-power network subsets across a range of traffic patterns. We implement and analyze ElasticTree on a prototype testbed built with production OpenFlow switches from three network vendors. Further, we examine the trade-offs between energy efficiency, performance and robustness, with real traces from a production e-commerce website. Our results demonstrate that for data center workloads, ElasticTree can save up to 50% of network energy, while maintaining the ability to handle traffic surges. Our fast heuristic for computing network subsets enables ElasticTree to scale to data centers containing thousands of nodes. We finish by showing how a network admin might configure ElasticTree to satisfy their needs for performance and fault tolerance, while minimizing their network power bill. <s> BIB002 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Software Defined Networking is a networking paradigm which allows network operators to manage networking elements using software running on an external server. This is accomplished by a split in the architecture between the forwarding element and the control element. Two technologies which allow this split for packet networks are For CES and Openflow. We present energy efficiency and resilience aspects of carrier grade networks which can be met by Openflow. We implement flow restoration and run extensive experiments in an emulated carrier grade network. We show that Openflow can restore traffic quite fast, but its dependency on a centralized controller means that it will be hard to achieve 50 ms restoration in large networks serving many flows. In order to achieve 50 ms recovery, protection will be required in carrier grade networks. <s> BIB003 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Ubiquitous sensing enabled by Wireless Sensor Network (WSN) technologies cuts across many areas of modern day living. This offers the ability to measure, infer and understand environmental indicators, from delicate ecologies and natural resources to urban environments. The proliferation of these devices in a communicating-actuating network creates the Internet of Things (IoT), wherein sensors and actuators blend seamlessly with the environment around us, and the information is shared across platforms in order to develop a common operating picture (COP). Fueled by the recent adaptation of a variety of enabling wireless technologies such as RFID tags and embedded sensor and actuator nodes, the IoT has stepped out of its infancy and is the next revolutionary technology in transforming the Internet into a fully integrated Future Internet. As we move from www (static pages web) to web2 (social networking web) to web3 (ubiquitous computing web), the need for data-on-demand using sophisticated intuitive queries increases significantly. This paper presents a Cloud centric vision for worldwide implementation of Internet of Things. The key enabling technologies and application domains that are likely to drive IoT research in the near future are discussed. A Cloud implementation using Aneka, which is based on interaction of private and public Clouds is presented. We conclude our IoT vision by expanding on the need for convergence of WSN, the Internet and distributed computing directed at technological research community. <s> BIB004 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Inter-domain routing is based on a fully decentralized model, where multiple Autonomous Systems (AS) interact via the BGP protocol. Although BGP is the "glue" of the Internet, it faces a lot of problems regarding its fully distributed nature, policy enforcement capabilities, scalability, security and complexity. Due to the widespread adoption of BGP, only incrementally deployable solutions are feasible. Taking this observation into account, we describe a new, backwards-compatible routing model which is based on outsourcing and logically centralizing the routing control plane. We claim that outsourcing enables enhanced inter-domain routing. As multiple ASes outsource their routing control plane to the same outsourcing service contractor, AS clusters are being gradually formed. A logically centralized multi-AS routing control platform based on Software Defined Networking (SDN) principles is the natural point for taking efficient routing decisions, detecting policy conflicts, troubleshooting routing problems, and evolving BGP. We present the technical and financial incentives which support the feasibility of the model and also propose an implementation scheme to facilitate it. <s> BIB005 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Offloading has emerged as a promising idea to allow resource-constrained mobile devices to access intensive applications, without performance or energy costs, by leveraging external computing resources. This could be particularly useful in enterprise contexts where running line-of-business applications on mobile devices can enhance enterprise operations. However, we must address three practical roadblocks to make offloading amenable to adoption by enterprises: (i) ensuring privacy and trustworthiness of offload, (ii) decoupling offloading systems from their reliance on the availability of dedicated resources and (iii) accommodating offload at scale. We present the design and implementation of ECOS, an enterprise-centric offloading framework that leverages Software-Defined Networking to augment prior offloading proposals and address these limitations. ECOS functions as an application running at an enterprise-wide controller to allocate resources to mobile applications based on privacy and performance requirements, to ensure fairness, and to enforce security constraints. Experiments using a prototype based on Android and OpenFlow establish the effectiveness of our approach. <s> BIB006 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> In this paper we present Vertigo (Virtual Topologies Generalization in OpenFlow networks), a Software-defined networking platform designed for network virtualization. Based on the OpenFlow original network slicing system Flow Visor, the Vertigo platform aims at covering all flavors of network virtualization: in particular, it is able to expose a simple abstract node on one extreme, and to deliver a logically fully connected network at the very opposite end. In this work, we first introduce the Vertigo system architecture and its design choices, then we report on a prototypical implementation deployed over an OpenFlow-enabled test bed. Experimental results show that Vertigo can deliver flexible and reliable network virtualization services to a wide range of use cases in spite of failure and/or congestion at the underlying physical network. <s> BIB007 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Reduction of unnecessary energy consumption is becoming a major concern in wired networking, because of the potential economical benefits and of its expected environmental impact. These issues, usually referred to as "green networking", relate to embedding energy-awareness in the design, in the devices and in the protocols of networks. In this work, we first formulate a more precise definition of the "green" attribute. We furthermore identify a few paradigms that are the key enablers of energy-aware networking research. We then overview the current state of the art and provide a taxonomy of the relevant work, with a special focus on wired networking. At a high level, we identify four branches of green networking research that stem from different observations on the root causes of energy waste, namely (i) Adaptive Link Rate, (ii) Interface proxying, (iii) Energy-aware infrastructures and (iv) Energy-aware applications. In this work, we do not only explore specific proposals pertaining to each of the above branches, but also offer a perspective for research. <s> BIB008 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Just like computation and storage, networks in data centers require virtualization in order to provide isolation between multiple co-existing tenants. Existing data center network virtualization approaches can be roughly divided into two generations: a first generation approach using simple VLANs and MAC addresses in various ways to achieve isolation and a second generation approach using IP overlay networks. These approaches suffer drawbacks. VLAN and MAC based approaches are difficult to manage and tie VM networking directly into the physical infrastructure, reducing flexibility in VM placement and movement. IP overlay networks typically have an relatively low scalability limit in the number of tenant VMs that can participate in a virtual network and problems are difficult to debug. In addition, none of the approaches meshes easily with existing provider wide area VPN technology, which uses MPLS. In this paper, we propose a third generation approach: multiple layers of tags to achieve isolation and designate routes through the data center network. The tagging protocol can be either carrier Ethernet or MPLS, both of which support multiple layers of tags. We illustrate this approach with a scheme called Zeppelin: packet tagging using MPLS with a centralized SDN control plane implementing Openflow control of the data center switches. <s> BIB009 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> We present the design, implementation, and evaluation of B4, a private WAN connecting Google's data centers across the planet. B4 has a number of unique characteristics: i) massive bandwidth requirements deployed to a modest number of sites, ii) elastic traffic demand that seeks to maximize average bandwidth, and iii) full control over the edge servers and network, which enables rate limiting and demand measurement at the edge. These characteristics led to a Software Defined Networking architecture using OpenFlow to control relatively simple switches built from merchant silicon. B4's centralized traffic engineering service drives links to near 100% utilization, while splitting application flows among multiple paths to balance capacity against application priority/demands. We describe experience with three years of B4 production deployment, lessons learned, and areas for future work. <s> BIB010 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> An important piece of the cellular network infrastructure is the radio access network (RAN) that provides wide-area wireless connectivity to mobile devices. The fundamental problem the RAN solves is figuring out how best to use and manage limited spectrum to achieve this connectivity. In a dense wireless deployment with mobile nodes and limited spectrum, it becomes a difficult task to allocate radio resources, implement handovers, manage interference, balance load between cells, etc. We argue that LTE's current distributed control plane is suboptimal in achieving the above objective. We propose SoftRAN, a fundamental rethink of the radio access layer. SoftRAN is a software defined centralized control plane for radio access networks that abstracts all base stations in a local geographical area as a virtual big-base station comprised of a central controller and radio elements (individual physical base stations). In defining such an architecture, we create a framework through which a local geographical network can effectively perform load balancing and interference management, as well as maximize throughput, global utility, or any other objective. <s> BIB011 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> With the rapid growth of the demands for mobile data, wireless network faces several challenges, such as lack of efficient interconnection among heterogeneous wireless networks, and shortage of customized QoS guarantees between services. The fundamental reason for these challenges is that the radio access network (RAN) is closed and ossified. We propose OpenRAN, an architecture for software-defined RAN via virtualization. It achieves complete virtualization and programmability vertically, and benefits the convergence of heterogeneous network horizontally. It provides open, controllable, flexible and evolvable wireless networks. <s> BIB012 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> We propose a network-driven transfer mode for cloud operations in a step towards a carrier SDN. Inter-datacenter connectivity is requested in terms of volume of data and completion time. The SDN controller translates and forwards requests to an ABNO controller in charge of a flexgrid network. <s> BIB013 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Software Defined Networking (SDN) is an emerging networking paradigm that separates the network control plane from the data forwarding plane with the promise to dramatically improve network resource utilization, simplify network management, reduce operating cost, and promote innovation and evolution. Although traffic engineering techniques have been widely exploited in the past and current data networks, such as ATM networks and IP/MPLS networks, to optimize the performance of communication networks by dynamically analyzing, predicting, and regulating the behavior of the transmitted data, the unique features of SDN require new traffic engineering techniques that exploit the global network view, status, and flow patterns/characteristics available for better traffic control and management. This paper surveys the state-of-the-art in traffic engineering for SDNs, and mainly focuses on four thrusts including flow management, fault tolerance, topology update, and traffic analysis/characterization. In addition, some existing and representative traffic engineering tools from both industry and academia are explained. Moreover, open research issues for the realization of SDN traffic engineering solutions are discussed in detail. <s> BIB014 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Software-defined network (SDN) has become one of the most important architectures for the management of largescale complex networks, which may require repolicing or reconfigurations from time to time. SDN achieves easy repolicing by decoupling the control plane from data plane. Thus, the network routers/switches just simply forward packets by following the flow table rules set by the control plane. Currently, OpenFlow is the most popular SDN protocol/standard and has a set of design specifications. Although SDN/OpenFlow is a relatively new area, it has attracted much attention from both academia and industry. In this paper, we will conduct a comprehensive survey of the important topics in SDN/OpenFlow implementation, including the basic concept, applications, language abstraction, controller, virtualization, quality of service, security, and its integration with wireless and optical networks. We will compare the pros and cons of different schemes and discuss the future research trends in this exciting area. This survey can help both industry and academia R&D people to understand the latest progress of SDN/OpenFlow designs. <s> BIB015 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> BGP severely constrains how networks can deliver traffic over the Internet. Today's networks can only forward traffic based on the destination IP prefix, by selecting among routes offered by their immediate neighbors. We believe Software Defined Networking (SDN) could revolutionize wide-area traffic delivery, by offering direct control over packet-processing rules that match on multiple header fields and perform a variety of actions. Internet exchange points (IXPs) are a compelling place to start, given their central role in interconnecting many networks and their growing importance in bringing popular content closer to end users. To realize a Software Defined IXP (an "SDX"), we need new programming abstractions that allow participating networks to create and run these applications and a runtime that both behaves correctly when interacting with BGP and ensures that applications do not interfere with each other. We must also ensure that the system scales, both in rule-table size and computational overhead. In this demo, we show how we tackle these challenges demonstrating the flexibility and scalability of our SDX platform. The paper also appears in the main program. <s> BIB016 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> The major challenge in future mobile networks is how to improve throughput to support the increase demand in traffic. Software Defined Networks is the new technology proposed but so far it has been proposed to be integrated in the current 4G architecture without major changes. However, we present the mobile networks beyond 4G where Software Defined Network should be used in a more disruptive approach to redesign the current architecture. This proposal includes the proper migration path to ensure reasonable transition phase. The objective is not to meet short term needs but to fulfill the future throughput requirements by revamping the transport network in the mobile backhaul, and moving most of the current LTE network elements to the cloud. In this approach we remove completely the core mobile network as it is known today. Instead, the mobile architecture beyond 4G consists of a simplified access network formed by base stations i.e. eNodeBs, interconnected through a backhaul network composed by SDN switches managed from the cloud together with the rest of LTE network elements. <s> BIB017 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> The meaning of 5G is still a subject of discussion in the industry. However, the softwarization of networks is expected to shape the design, operation and management of 5G networks. The opportunity is then crucial for Telcos, vendors and IT players to consider the management of 5G networks during its design time and avoid the “build it first, manage it later” paradigm. However, network softwarization comes with its own set of challenges, including robustness, scalability and resilience. In this paper, we analyze the vulnerabilities of SDN (Software-Defined Networks) and NFV (Network Function Virtualization) from a fault management perspective, while taking into account the autonomic principles. In particular, we focus on resiliency and we propose a Self-Healing based framework for 5G networks to ensure services and resources availability. <s> BIB018 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Mobile devices interact wirelessly with a growing proliferation of cloud-based applications. Due to significant traffic growth and a wide variety of multimedia solutions, enterprise IT departments are demanding more fine-grained visibility and control of mobile traffic. They want to deliver optimal performance and a high quality of experience to a variety of users and applications. In the wired world, Software-Defined Networking (SDN) is a technology being embraced to deliver performance guarantees to end users by dynamically orchestrating quality of service (QoS) policies on edge switches and routers. Guaranteeing performance in a wired access network does not require any network control on clients, because the last hop between the network edge and wired device is a dedicated point-to-point link (e.g. Ethernet). However, this is not the case with wireless LANs (WLAN), since the last hop is a shared half-duplex medium and the WiFi MAC protocol does not allow access points to coordinate client uplink transmissions or 802.11 QoS settings. Hence, we argue that the SDN paradigm needs to be extended to mobile clients to provide optimal network performance between the cloud and wirelessly-connected clients. In this paper, we propose a framework called meSDN and demonstrate that it enables WLAN virtualization, application-aware QoS and improves power-efficiency from our prototype on Android phones. <s> BIB019 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> This paper describes a demonstration of SDN-based optical transport network virtualization and orchestration. Two scenarios are demonstrated: a dynamic setup of optical connectivity services inside a single domain as well as a multidomain service orchestration over a shared optical infrastructure using the architecture defined in the STRAUSS project. <s> BIB020 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> The ossified architecture and widespread application of the internet have restricted its development For overcoming the existing obstacles of network innovation and management, network virtualization and autonomie management have been proposed. However, these two attractive technologies are subjected to the headaches of updating various devices. Software-Defined Networking (SDN) separates the control plane from the data plane. Therefore, some network control and management functions could be implemented through softwares. This provides a chance for the network virtualization and autonomie management In this paper, a SDN-based network Virtualization architecture with Autonomie management (SDNVA) is proposed. The SDNVA architecture enables heterogeneous virtual networks to coexist on the same physical network, and supports hierarchical autonomie management. Moreover, we evaluate SDNVA on our testbed and find that the SDNVA architecture can perceive topology changes and isolate multiple virtual networks. <s> BIB021 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> This SpringerBrief presents adaptive resource allocation schemes for secondary users for dynamic spectrum access (DSA) in cognitive radio networks (CRNs) by considering Quality-of-Service requirements, admission control, power/rate control, interference constraints, and the impact of spectrum sensing or primary user interruptions. It presents the challenges, motivations, and applications of the different schemes. The authors discuss cloud-assisted geolocation-aware adaptive resource allocation in CRNs by outsourcing computationally intensive processing to the cloud. Game theoretic approaches are presented to solve resource allocation problems in CRNs. Numerical results are presented to evaluate the performance of the proposed methods. Adaptive Resource Allocation in Cognitive Radio Networks is designed for professionals and researchers working in the area of wireless networks. Advanced-level students in electrical engineering and computer science, especially those focused on wireless networks, will find this information helpful. <s> BIB022 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> SDN proposes a logically centralized architecture where the control entity (SDN controller) is responsible for providing an abstraction of network resources through Application Programming Interfaces (API). This abstraction enables SDN to perform network virtualization, that is, to slice the physical infrastructure and create multiple co-existing network slices (virtual networks) independent of the underlying wireless or optical technology and network protocols. Ideally, the SDN architecture is based on a single control domain comprising multiple network nodes featuring diverse technologies provided by different vendors that are controlled through standard interfaces. However, transport network operators usually fragment their networks into multiple domains to cope with administrative and regional organizations. Each domain can be provided by a different vendor with its own control plane technology (SDN/OpenFlow with some proprietary extensions, legacy GMPLS/PCE, MPLS control, etc.). This paper presents the architecture of SDN orchestration and virtualization proposed in the STRAUSS project. The proposed architecture provides a unified transport network operating system allowing the composition, at a an abstracted level, of end-to-end virtual transport networks as well as end-to-end provisioning services across multiple domains with heterogeneous control and transport technologies. <s> BIB023 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> As a promising paradigm for fifth generation wireless communication systems, cloud radio access networks (C-RANs) have been shown to reduce both capital and operating expenditures, as well as to provide high spectral efficiency (SE) and energy efficiency (EE). The fronthaul in such networks, defined as the transmission link between the baseband unit and the remote radio head, requires a high capacity, but is often constrained. This article comprehensively surveys recent advances in fronthaul-constrained CRANs, including system architectures and key techniques. Particularly, major issues relating to the impact of the constrained fronthaul on SE/EE and quality of service for users, including compression and quantization, large-scale coordinated processing and clustering, and resource allocation optimization, are discussed together with corresponding potential solutions. Open issues in terms of software-defined networking, network function virtualization, and partial centralization are also identified. <s> BIB024 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> In this paper, we investigate a two-stage Stackelberg game for dynamic spectrum access (DSA) in cognitive radio networks using a leader [spectrum provider (SP)] subgame and a follower [secondary user (SU)] subgame. Our research distinguishes itself in a number of ways. First, a two-stage Stackelberg game has been proposed to provide a unique optimal solution that facilitates a tradeoff between quality of service (QoS) of unlicensed SUs and revenue of SPs. Second, comprehensive budget and QoS constraints imposed by the signal-to-interference-plus-noise ratio are defined to fully take into account QoS requirements. Third, a necessary condition and closed form for the existence of the Stackelberg equilibrium are presented for multiradio multichannel DSA. Analytical and simulation studies are carried out to assess the performance of the proposed game, and the numerical results verify that the proposed approach reaches the unique Stackelberg equilibrium. <s> BIB025 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> C. Applications of SDN <s> Virtualization is emerging as an efficient resource utilization method that eliminates dedicated physical devices. Virtualization has been widely used in computer systems such as virtual memory, virtual storage access network and wired networks - and most recently in cloud computing - to enhance the network performance, resource utilization and energy efficiency, and to achieve performance isolation between different parties. Inspired by this, several techniques for network and wireless virtualization have been proposed in the literature in order to improve the network performance and security. In this paper, we provide a comprehensive study of network and wireless virtualization for enhancing overall network security. We also outline current state of the research and future perspectives. With this paper, readers can have a more thorough understanding of wireless virtualization for network security and the research trends in this area. <s> BIB026
Data centers are the major places used for storage of information/data. The structure of data centers in conventional networks is complex and difficult to manage. The available resources are not properly utilized as it does not have a complete view of the network. The data centers implemented using SDN can dynamically adapt by expanding or shrinking its size based on the requirement. Global view feature in SDN can be used for efficient traffic management to improve the overall network performance and resource utilization, and reduce the energy consumption of the network. Upgrading in traditional networks is not only associated with a cost of replacing the entire network but also involves the chance of losing important information. SDN is capable of upgrading the data-centers without loosing the information, changing the overall work flow in the network and degrading the overall performance BIB013 - BIB009 . The usage of SDN in WAN gained significant attention with Google deploying it for managing their data centers. Google employed traffic engineering schemes and were able to get benefits such as fault tolerance, active link utilization up to 100% promoting energy efficiency BIB010 . Software driven WAN (SWAN) offers flexibility to optimize the network policies and handle flows based on the priority set by the client and Top-level wireless virtualization architecture with SDN BIB025 , BIB022 , BIB026 . was able to offer 38% more throughput than MLPS (Multi Layer Protocol Switching) scheme BIB014 . Note that the MLPS traffic engineering was the most commonly adopted method in conventional networks. Exponential growth of connected devices for IoT and cyber-physical systems BIB004 can be handled by SDN by expanding and/or shrinking resources on the fly BIB015 , BIB016 , BIB005 . SDN in Cellular Networks offers centralized control for cost-effective solutions for reducing Capital expenditures (CAPEX) and operating expenses (OPEX) of the cellular network. Combination of cellular networking technologies and SDN can offer high data rate and better QoS to the users BIB017 ,  . One of the major benefits is its capability to allow switching between different wireless technologies to provide better connectivity and coverage  , BIB025 . Failure recovery, availability, dependability and security can be improved in cellular system BIB018 , BIB006 . SDN for Wi-Fi Network effectively guarantees airtime shares to network slices using a Time Division Multiple Access (TDMA) like airtime scheduling BIB019 . Furthermore, SDN provides the flexibility for the deployment of Wi-Fi infrastructure in the rural areas where the traditional networks are hard to deploy and manage BIB019 , BIB001 . SDN offers network interface for heterogeneous transport networks through virtualization (e.g., BIB023 ) and for optical network virtualization in BIB020 . The management and allocation of resources to virtual networks/machines is simplified by introducing ANM (Automatic Network Management) systems in the design BIB021 - BIB007 . In order to have seamless switching (aka wireless virtualization) between different wireless technologies such as satellite, cellular, TV, GPS, Wi-Fi, etc., Cloud-base Radio Access Networks (C-RAN) has been proposed in BIB022 . A typical block diagram for C-RAN is shown in Fig. 4 . SoftRAN has been proposed to provide reliable connectivity and coverage with available spectrum in BIB011 . Furthermore, for Self Organizing Network (SON) in C-RAN, Heterogeneous Cloud Radio Access Networks (HC-RAN) are capable of supporting the decoupling without degrading the overall network performance BIB024 ,  . Similarly, OpenRAN has been proposed for deployment of SDN in C-RAN for meeting the QoS requirements using Wireless Spectrum Resource Pool (WSRP), SDN controller and Cloud Computing Resource Pool (CCRP) BIB012 . Due to ease to modify the system and adapt various energy efficient mechanisms, SDN provides a better solution for green networking which has become important in network design and deployment for economic and environmental benefits. For green networking, there have been different approaches considered BIB008 . It is noted that SDN switching devices may not directly help reduce energy consumption in the SDN-based networks BIB003 , however SDN offers configurations that can help to reduce energy consumption BIB008 , BIB002 . Further details for green networking using SDN are presented in Section IV of this paper.