In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the grow...In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.展开更多
The healthcare sector holds valuable and sensitive data.The amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast pace.Due to their nature,software-defined networks(SDNs)are ...The healthcare sector holds valuable and sensitive data.The amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast pace.Due to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and monitoring.In this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe attacks.These attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human lives.This can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or m-health.In this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various scenarios.We propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS attack.We then evaluate the accuracy and performance of the proposed TBDC approach.Our technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.展开更多
分布式移动管理(DMM,distributed mobility management)是解决移动切换问题的有效方法之一,因此,被认为是能够应用于卫星网络移动性管理的技术。提出了一种基于DMM的软件定义网络(SDN,software defined network)的分布式移动管理方案,...分布式移动管理(DMM,distributed mobility management)是解决移动切换问题的有效方法之一,因此,被认为是能够应用于卫星网络移动性管理的技术。提出了一种基于DMM的软件定义网络(SDN,software defined network)的分布式移动管理方案,来解决卫星网络中的流量重定向问题。与传统DMM应用场景即基于网络或基于终端不同,SDN-DMM方案在SDN控制器中实现位置管理和地址切换。因此,基于SDN的卫星网路分布式移动管理方案相比于传统的方案可以实现分组转发路径优化,并在网络开销和流量管理方面表现出显著的优势。展开更多
直流配电系统是未来配电系统的发展趋势,大规模分布式能源接入是未来配电系统的重要特征。针对含软联络开关(soft open point,SOP)和电压源变流器(voltage source converter,VSC)的交直流混合配电系统,考虑分布式能源大规模接入引起的...直流配电系统是未来配电系统的发展趋势,大规模分布式能源接入是未来配电系统的重要特征。针对含软联络开关(soft open point,SOP)和电压源变流器(voltage source converter,VSC)的交直流混合配电系统,考虑分布式能源大规模接入引起的网络阻塞问题,提出了一种两阶段阻塞管理机制。在第一阶段,考虑交直流混合配电网中SOP、VSC及联络开关等可直接控制资源的优化调节能力,建立多资源协调优化调度模型。在第二阶段,考虑直接控制资源调节能力的限制,利用新能源电站、电动汽车充电站以及可调负荷等灵活性资源,以配电公司成本最低为优化目标建立阻塞管理控制模型。算例结果表明,所提出的阻塞管理机制,能够充分利用交直流混合配电网的优势,消除网络阻塞风险,降低阻塞管理成本,提高分布式能源的渗透率。展开更多
基金This work is supported by the Fundamental Research Funds for the Central Universities.
文摘In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.
基金extend their appreciation to Researcher Supporting Project Number(RSPD2023R582)King Saud University,Riyadh,Saudi Arabia.
文摘The healthcare sector holds valuable and sensitive data.The amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast pace.Due to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and monitoring.In this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe attacks.These attacks reduce network performance,causing the degradation of different key performance indicators(KPIs)or,in the worst cases,a network failure which can threaten human lives.This can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or m-health.In this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KPIs under various scenarios.We propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS attack.We then evaluate the accuracy and performance of the proposed TBDC approach.Our technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.
文摘分布式移动管理(DMM,distributed mobility management)是解决移动切换问题的有效方法之一,因此,被认为是能够应用于卫星网络移动性管理的技术。提出了一种基于DMM的软件定义网络(SDN,software defined network)的分布式移动管理方案,来解决卫星网络中的流量重定向问题。与传统DMM应用场景即基于网络或基于终端不同,SDN-DMM方案在SDN控制器中实现位置管理和地址切换。因此,基于SDN的卫星网路分布式移动管理方案相比于传统的方案可以实现分组转发路径优化,并在网络开销和流量管理方面表现出显著的优势。
文摘直流配电系统是未来配电系统的发展趋势,大规模分布式能源接入是未来配电系统的重要特征。针对含软联络开关(soft open point,SOP)和电压源变流器(voltage source converter,VSC)的交直流混合配电系统,考虑分布式能源大规模接入引起的网络阻塞问题,提出了一种两阶段阻塞管理机制。在第一阶段,考虑交直流混合配电网中SOP、VSC及联络开关等可直接控制资源的优化调节能力,建立多资源协调优化调度模型。在第二阶段,考虑直接控制资源调节能力的限制,利用新能源电站、电动汽车充电站以及可调负荷等灵活性资源,以配电公司成本最低为优化目标建立阻塞管理控制模型。算例结果表明,所提出的阻塞管理机制,能够充分利用交直流混合配电网的优势,消除网络阻塞风险,降低阻塞管理成本,提高分布式能源的渗透率。
