Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> F. Optimal Location of SDN Devices <s> The exponential growth of devices connected to the network has resulted in the development of new IoT applications and on-line services. However, these advances are limited by the rigidity of the current network infrastructure, in which the administrator has to implement high-level network policies adapting and configuring protocols manually and usually through a command line interface (CLI). At this point, Software-Defined Networking (SDN) appears as a viable alternative network architecture that allows for programming the network and opening the possibility of creating new services and more efficient applications to cover the actual requirements. In this paper, we describe this new technology and analyze its opportunities in the development of IoT applications. Similarly, we present the first applications and projects based on this technology. Finally, we discuss the issues and challenges in its implementation. <s> BIB001 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> F. Optimal Location of SDN Devices <s> The growing interest in the Internet of Things (IoT) has resulted in a number of wide-area deployments of IoT subnetworks, where multiple heterogeneous wireless communication solutions coexist: from multiple access technologies such as cellular, WiFi, ZigBee, and Bluetooth, to multi-hop ad-hoc and MANET routing protocols, they all must be effectively integrated to create a seamless communication platform. Managing these open, geographically distributed, and heterogeneous networking infrastructures, especially in dynamic environments, is a key technical challenge. In order to take full advantage of the many opportunities they provide, techniques to concurrently provision the different classes of IoT traffic across a common set of sensors and networking resources must be designed. In this paper, we will design a software-defined approach for the IoT environment to dynamically achieve differentiated quality levels to different IoT tasks in very heterogeneous wireless networking scenarios. For this, we extend the Multinetwork INformation Architecture (MINA), a reflective (self-observing and adapting via an embodied Observe-Analyze-Adapt loop) middleware with a layered IoT SDN controller. The developed IoT SDN controller originally i) incorporates and supports commands to differentiate flow scheduling over task-level, multi-hop, and heterogeneous ad-hoc paths and ii) exploits Network Calculus and Genetic Algorithms to optimize the usage of currently available IoT network opportunities. We have applied the extended MINA SDN prototype in the challenging IoT scenario of wide-scale integration of electric vehicles, electric charging sites, smart grid infrastructures, and a wide set of pilot users, as targeted by the Artemis Internet of Energy and Arrowhead projects. Preliminary simulation performance results indicate that our approach and the extended MINA system can support efficient exploitation of the IoT multinetwork capabilities. <s> BIB002 </s> Software Defined Networking Architecture, Security and Energy Efficiency: A Survey <s> F. Optimal Location of SDN Devices <s> Future power systems are characterized by a high degree of complexity with a large number of intelligent devices, exchanging and processing both huge amounts of data and realtime critical information. Accordingly reliable, real-time capable and secure communication networks are required for enabling autonomous monitoring, management and control to guarantee stable power system operation. In this paper, we present and analyse a flexible and dynamic network control approach based on Software-Defined Networking (SDN) for meeting the specific communication requirements of both distribution and transmission power grid. Therefore a testbed is introduced, enabling the evaluation of multiple failure scenarios such as link disturbance and congestion by analysing corresponding fast recovery and prioritization solutions. The performance and robustness of the developed strategies is shown using highly-critical monitoring and control messages on basis of IEC 61850 and considering the mutual impact with low priority background traffic. Results indicate the advantages of SDN compared to traditional routing and Quality-of-Service mechanisms, providing a more reliable communication network, which is able to handle complex failure scenarios. In particular, SDN enables the integration of diverse network management functions and thus offers the power system new options for dealing with faults even in the case of overall outages. On the basis of these results, we demonstrate challenges and derive future benefits for a SDN-enabled Smart Grid communication network, holding the potential to evolve into a self-healing infrastructure. <s> BIB003
Optimization for placement of SDN controller, SDN switches and other end devices is another open problem in SDN as placement of different SDN devices impacts the overall network performance and security. It would be more important to enable more efficient network resource sharing and improve services for trillions devices in Internet of Things applications BIB001 , BIB002 . Note that the selection of different parameters depends on the application that the SDN is envisioned to support. For instance, optimal parameters in SDN for smart grid may not be optimal SDN parameters for traditional data center networks BIB003 , optimal SDN for IoT may not be optimal SDN for cyber-physical systems, and so on.