A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> The rapid increase in network traffic with new bandwidth-hungry applications such as cloud computing and telemedicine makes disaster survivability a crucial concern as the data (and revenue) loss caused by large-scale correlated cascading failures can be very high. To alleviate their impact, new measures should be taken since the nature of the network changes dramatically as available resources decrease during disasters. We develop a metric, called degraded-service tolerance, which can reduce protection cost and network disruption, and support maximal carried traffic in case of disasters. Degraded-service-tolerant connections can be admitted and recovered with reduced bandwidth under resource crunch. Our scheme re-assigns resources among connections by leveraging their degraded-service tolerance. A case study shows how our proposal can be applied to boost network performance during the resource crunch following a disaster. <s> BIB001 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Emerging trends in cyber system security breaches, including those in critical infrastructures involving cloud systems, such as in applications of military, homeland security, finance, utilities and transportation systems, have shown that attackers have abundant resources, including both human and computing power, to launch attacks. The sophistication and resources used in attacks reflect that the attackers may be supported by large organizations and in some cases by foreign governments. Hence, there is an urgent need to develop intelligent cyber defense approaches to better protecting critical cloud infrastructures. In order to have much better protection for critical cloud infrastructures, effective approaches with predictive capability are needed. Much research has been done by applying game theory to generating adversarial models for predictive defense of critical infrastructures. However, these approaches have serious limitations, some of which are due to the assumptions used in these approaches, such as rationality and Nash equilibrium, which may not be valid for current and emerging cloud infrastructures. Another major limitation of these approaches is that they do not capture probabilistic human behaviors accurately, and hence do not incorporate human behaviors. In order to greatly improve the protection of critical cloud infrastructures, it is necessary to predict potential security breaches on critical cloud infrastructures with accurate system-wide causal relationship and probabilistic human behaviors. In this paper, the challenges and our vision on developing such proactive protection approaches are discussed. <s> BIB002 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Load balancing is critical in complex naval networks to provide reliable performance by ensuring the system is not over-loaded and by high resource utilization. Load balancing guarantees the stability of a naval ship tactical network in a distributed environment. Tactical networks are highly dynamic due to mission requirements, policies, or environment condition. There is never enough bandwidth for data-intensive military operations. Additional challenges of tactical environments are limited bandwidth, and intermittent connectivity caused by battle space condition. In this paper, we present our approach to create a benchmark to evaluate load balancing with OpenFlow protocol of SDN technology for a Navy scenario. Our results show that SDN technology offers agility and flexibility to configure, and manage the network. <s> BIB003 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Current implementations of Internet systems are very hard to be upgraded. The ossification of existing standards restricts the development of more advanced communication systems. New research initiatives, such as virtualization, software-defined radios, and software-defined networks, allow more flexibility for networks. However, until now, those initiatives have been developed individually. We advocate that the convergence of these overlying and complementary technologies can expand the amount of programmability on the network and support different innovative applications. Hence, this paper surveys the most recent research initiatives on programmable networks. We characterize programmable networks, where programmable devices execute specific code, and the network is separated into three planes: data, control, and management planes. We discuss the modern programmable network architectures, emphasizing their research issues, and, when possible, highlight their practical implementations. We survey the wireless and wired elements on the programmable data plane. Next, on the programmable control plane, we survey the divisor and controller elements. We conclude with final considerations, open issues and future challenges. <s> BIB004 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> The world security context is changing more than ever. Military interest has shifted from the conventional means of warfare to that of cyber warfare. The most potent nations have entire armies that are watching the international cyberspace for anomalies. And these forces are ready to intervene for keeping peace at home or for an enemy nation. The international interest in exploit development has risen significantly. And has gone from an underground activity of a group of hackers to a semi-covert operation of a governmental agency [1]. In this context, where over 70 exabytes of data are moved over the internet, per month [2], and the level of significant cyber-attacks is almost 43 million per year [3] the sheer number of security events a SIEM operator has to triage can be impressive and overwhelming. This is why a human operator has to be helped by technology. This is where neural networks can bring a huge plus for detecting previously unknown attacks and zero-day exploits. And visual analytics to help a human being understand and process the huge volume of information coming to him, by presenting it in a cognitive fashion that helps him better understand and classify it in the correct context. Both of the concepts evoked are presented in this paper, the detection algorithm based on neural networks and the scientific representation scheme based on visual analytics. <s> BIB005 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Resilience against disaster scenarios is essential to network operators, not only because of the potential economic impact of a disaster but also because communication networks form the basis of crisis management. COST RECODIS aims at studying measures, rules, techniques and prediction mechanisms for different disaster scenarios. This paper gives an overview of different solutions in the context of technology-related disasters. After a general overview, the paper focuses on resilient Software Defined Networks. <s> BIB006 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> This paper proposes an efficient load balancing scheme for distributed controller in Software-Defined Networking-based mission-critical networks. Based on load status and dynamic weight coefficient on each controller, the proposed scheme guarantees load balancing in control plane to achieve better resource usage, reliability and resilience in the network. Furthermore, by using pre-defined load threshold, communication overhead is significantly reduced in comparison with existing approaches. Simulation results demonstrate that the proposed scheme is effective in terms of communication overhead and performance of load balancing in the control plane. <s> BIB007 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Emergency Rescue Information Sharing System supports rescue operations in early stage by gathering information about victims in need of help at the time of disaster. In this system, in-vehicle relays are used to gather extensive information. In-vehicle relays transmit information sent by mobile terminals to a database server via gateway switches. There are several wireless connections between relays and gateway switches to make the transmission redundant. However, information loss occurs when all links are disconnected. In addition, mobile terminals cannot send information without available wireless connections. In this paper, we propose a disaster information gathering mechanism that adopts Web-based offline operation and OpenFlow-based routing control. Offline operation of the system is realized by information caching and synchronization. Wireless links between in-vehicle relays and gateway switches are controlled by OpenFlow. Our mechanism selects a link for transmission dynamically in response to the status and priority changes of the wireless links. In order to prevent information loss while relays isolated from networks, information from mobile terminals is temporarily stored in in-vehicle servers. Prototype demonstration shows that the proposed mechanism can achieve high information gathering rate at the database server. <s> BIB008 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Hijacks, outages, route leaks, and AS path spoofing are cases where network operators may want to influence the way routes are accepted and propagated from BGP neighbors in ways not supported by traditional BGP speakers. In this paper, we introduce Bongo, a software-based BGP speaker than can selectively filter out or extend the path of BGP updates received from other peers based on arbitrary operator-defined policies. Additionally, we show how the modularity of this system makes it easy to integrate with existing routers as well as other network devices such as OpenFlow switches or firewalls. <s> BIB009 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> We are witnessing the evolution of optical networks toward highly heterogeneous, flexible networks with a widening area of application. As the bandwidth and reliability performance requirements of mission-critical applications tighten, and the amount of carried data grows, issues related to optical network security are becoming increasingly important. Optical networks are vulnerable to several types of attacks at the physical layer, typically aimed at disrupting the service or gaining unauthorized access to carried data. Such security breaches can induce financial losses to clients or loss of privacy, or cause network-wide service disruption, possibly leading to huge data and revenue losses. Awareness of system weaknesses and possible attack methods is a prerequisite for designing effective network security solutions. As optical networks evolve, new and changing vulnerabilities must be identified and dealt with efficiently. To this end, this article provides a comprehensive overview of potential physical-layer attack scenarios in current and future optical networks. It then proposes a general security framework, outlining possible strategies for dealing with such attacks, meant to aid in the development of efficient provisioning, monitoring, protection, and restoration schemes in the context of optical-layer security. <s> BIB010 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Securing Internet of Things is a challenge because of its multiple points of vulnerability. In particular, Distributed Denial of Service (DDoS) attacks on IoT devices pose a major security challenge to be addressed. In this paper, we propose a DNS query-based DDoS attack mitigation system using Software-Defined Networking (SDN) to block the network traffic for DDoS attacks. With some features provided by SDN, we can analyze traffic patterns and filter suspicious network flows out. To show the feasibility of the proposed system, we particularly implemented a prototype with Dirichlet process mixture model to distinguish benign traffic from malicious traffic and conducted experiments with the dataset collected from real network traces. We demonstrate the effectiveness of the proposed method by both simulations and experiment data obtained from the real network traffic traces. <s> BIB011 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> This study addresses the issues of optical network survivability to attacks in the optical physical layer. The authors comprehensively review and discuss the vulnerability of optical networks towards various types of security threats that could appear in the network optical layer: passive eavesdropping attacks and active optical attacks like in-band jamming, out-of-band crosstalk attacks, amplifier attacks and physical infrastructure attacks. They describe and discuss several protection procedures and monitoring techniques to improve network attack survivability. Numerical simulation performances of some attacks and protection schemes are also provided. <s> BIB012 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> Network resilience against failures due to natural disasters, equipment malfunction, and malicious attacks has become important for software-defined networks. The current state of the art focuses on two directions: controller redundancy and related recovery mechanisms for resilience in the control plane, and reactive or proactive strategies for resilience against failure of switches or links in the data plane. However, proactive network topology resilience against multiswitch failure by installing backup switches at key locations has been overlooked. We propose a proactive network-topology resilience scheme against worst case adversarial multiswitch failures by installing backup switches at key locations to maximize long-term traffic demands. We formulate this problem as a trilevel optimization, which helps the network operator identify the key N positions for installing backup switches. We develop mixed integer linear programming formulations to maximize aggregate demand satisfaction and maximize the minimum fair demand satisfaction while satisfying constraints such as connectivity, control-plane latency limits, and association capacity of controllers. The proposed models are NP-hard; therefore, we propose efficient heuristic-based greedy algorithms to solve large instances of the above-mentioned problems. We implement the proposed solutions and present the numerical results, which show optimality of the exact formulations and efficiency of the greedy algorithms. <s> BIB013 </s> A Systematic Literature Review on Military Software Defined Networks <s> SDN Control Plane Resilience and Security <s> The ease of programmability in Software-Defined Networking (SDN) makes it a great platform implementation of various initiatives that involve application deployment, dynamic topology changes, and decentralized network management in a multi-tenant data center environment. However, implementing security solutions in such an environment is fraught with policy conflicts and consistency issues with the hardness of this problem being affected by the distribution scheme for the SDN controllers. In this paper we present Brew, a security policy analysis framework implemented on an OpenDaylight SDN controller, that has comprehensive conflict detection and resolution modules to ensure that no two flow rules in a distributed SDN-based cloud environment have conflicts at any layer; thereby assuring consistent conflict-free security policy implementation and preventing information leakage. We present techniques for global prioritization of flow rules in a decentralized environment, extend firewall rule conflict classification from a traditional environment to SDN flow rule conflicts by recognizing and classifying conflicts stemming from cross-layer conflicts and provide strategies for unassisted resolution of these conflicts. Alternately, if administrator input is desired to resolve conflicts, a novel visualization scheme is implemented to help the administrators view the conflicts graphically. We demonstrate the correctness, feasibility and scalability of our framework through a proof-of-concept prototype. <s> BIB014
Machuca et al. BIB006 presented a survey of disaster resilient SDN networks that is transferable to the military context. The survey points out unresolved issues concerning security considerations and disaster scenarios. To overcome the single point of failure (SPoF) of a network controller, multi-controller and multi-domain topologies have been suggested, but, according to the author, this approach introduces a new security problem on the orchestration and management layers. Trends of cloud computing services also apply to military services, where SDN networks with one network controller often are pointed out as a critical part of the infrastructure BIB002 . Hai et al. BIB007 suggests an efficient way to overcome the SPoF problem by putting a redundant load balancer in front of a pair of network controllers. However, multi-controller orchestration is not mentioned in the article. A similar approach was also demonstrated by Dilmaghani et al. BIB003 (see Section 4.5) that presented an SDN load balancing design for naval networks. In military networks, it is critical to maintain access to network services, especially under disasters and critical operations. The SPoF problem does not only concern the availability and the load on the controller, but it also applies when the network devices do not have network connectivity to the controller. Distributed content caching in vehicles, can assure that information can be distributed to devices around the vehicles if the vehicles lose up-link network connections. Tabata et al. BIB008 suggests to use many distributed SDN controllers and to alter the OpenFlow rules during online and offline caching operations. The paper demonstrates the concept, but it introduces a security concern due to operating multiple SDN domains that is not mentioned in the article. However, Macedo et al. BIB004 presents a survey of the relationship between SDR, SDN and NFV and points out security and inter-domain communication of SDN controllers as the main research challenges, something that is also transferable to the military context. Sorensen et al.  showed how SDN in a federated network can enforce network policy control across domain borders in military networks. However, in a multi-domain SDN topology with distributed SDN controllers, the SDN flow rules can come in conflict with each other. In networks such as military networks, security precedence can have higher prioritization than the current OpenFlow specification allows. The authors of an architecture named Brew BIB014 suggested to extend the OpenFlow specification in order to calculate reconciliations of conflicting SDN rules between controllers. In addition to conflicting rules, the integrity of the rules is also pointed out as a security weakness in multi-domain topologies. This is presented by Beton et al. BIB009 who is suggesting to use a BGP route reflector with route filtering capabilities based on allocation, reputation and path analysis. SDN with OpenFlow can then contribute to making route filtering policies. However, Porras et al.  also show that within a single OpenFlow domain, multiple SDN applications must also meet stringent security requirements. The authors here presented a security framework to handle conflicting SDN rules between different applications. Furthermore, Ahmed et al. BIB011 focused on mitigating DNS Query-Based DDoS Attacks with machine learning on SDN, and implemented a prototype based on traffic features using Dirichlet process mixture model (DPMM) for clustering traffic applications flow, including those used for DDoS attacks in an unsupervised manner. Designing a critical infrastructure topology also includes placing network devices strategically, in order to achieve network redundancy and to have backup sites ready when disaster happens. Ashraf et al. BIB013 suggests utilizing SDN flow-rule parameters combined with monitoring, in order to calculate where it is most efficient to place backup switches to make the network more resilient. Savas et al. BIB001 suggested a procedure for dynamically setting up a full network on a new site after a disaster, where the use of SDN can accelerate the provisioning time. The procedure includes a recovery provisioning, an upgrade procedure, and a prioritization policy for network resources. Making a resilient SDN network also includes operational management tools to ensure attack protection of the SDN controller. Ionita et al. BIB005 shows that SDN networks are vulnerable, and that there is a need for additional visual analytics tools for protection against the new threats arising from SDN, such as Denial of Service attacks towards network controllers. Skoin et al. BIB010 points out a set of physical infrastructure attacks such as wiretapping, electromagnetic pulses (EMP), and critical hub nodes "take-out". The author suggest that centralization of network controllers in OpenFlow introduces new vulnerabilities and makes security even more complex. Correspondingly, Dahan et al. BIB012 pinpoint that the network controllers must be both secured from passive and active attacks, as well as physical and network attacks.