Large latency of applications will bring revenue loss to cloud infrastructure providers in the cloud data center. The existing controllers of software-defined networking architecture can fetch and process traffic info...Large latency of applications will bring revenue loss to cloud infrastructure providers in the cloud data center. The existing controllers of software-defined networking architecture can fetch and process traffic information in the network. Therefore, the controllers can only optimize the network latency of applications. However, the serving latency of applications is also an important factor in delivered user-experience for arrival requests. Unintelligent request routing will cause large serving latency if arrival requests are allocated to overloaded virtual machines. To deal with the request routing problem, this paper proposes the workload-aware software-defined networking controller architecture. Then, request routing algorithms are proposed to minimize the total round trip time for every type of request by considering the congestion in the network and the workload in virtual machines（VMs）. This paper finally provides the evaluation of the proposed algorithms in a simulated prototype. The simulation results show that the proposed methodology is efficient compared with the existing approaches.展开更多
Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challe...Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network（SDWN）, and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is proposed.Simulations demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance.展开更多
针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源...针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源头主机;然后,由控制器制定动态限制策略对连接攻击源头主机的交换机端口的新流转发功能进行限制,待限制期满再恢复其转发新流的功能,限制期的大小随着被检测为攻击源的次数而增长。研究结果表明:这种动态的限制策略可阻隔攻击流进入SDN网络,从而有效避免SDN交换机、控制器以及链路过载;由于在限制期间无需再对这些限制的交换机端口进行实时监测,该方法在应对长时攻击时较传统方法具有更高的缓解效率和更少的资源消耗。展开更多
面向开源项目推荐开发人员对开源生态建设具有重要意义。区别于传统软件开发,开源领域的开发者、项目、组织及相互关系体现了开放式协作项目的特点,而它们蕴含的语义有助于精准推荐开源项目的开发者。因此,提出一种基于协作贡献网络(CCN...面向开源项目推荐开发人员对开源生态建设具有重要意义。区别于传统软件开发,开源领域的开发者、项目、组织及相互关系体现了开放式协作项目的特点,而它们蕴含的语义有助于精准推荐开源项目的开发者。因此,提出一种基于协作贡献网络(CCN)的开发者推荐(DRCCN)方法。首先,利用开源软件(OSS)开发者、OSS项目、OSS组织之间的贡献关系构建CCN;其次,基于CCN构建一个3层深度的异构GraphSAGE(Graph SAmple and aggreGatE)图神经网络(GNN)模型,预测开发者节点和开源项目节点之间的链接,从而产生相应的嵌入对;最后,根据预测结果,采用K最近邻(KNN)算法完成开发者推荐。在GitHub数据集上训练和测试模型的实验结果表明,相较于序列推荐的对比学习模型CL4SRec(Contrastive Learning for Sequential Recommendation),DRCCN在精确率、召回率和F1值这3个指标上分别提升了约10.7%、2.6%和4.2%。因此,所提模型可以为开源社区项目的开发者推荐提供重要的参考依据。展开更多
针对工业物联网中业务需求多样性和服务质量(Quality of Service,QoS)要求差异性导致的网络资源利用低问题,提出一种基于深度强化学习的网络切片资源分配策略。该策略运用深度强化学习优化网络切片资源分配的准入控制,通过智能体在特定...针对工业物联网中业务需求多样性和服务质量(Quality of Service,QoS)要求差异性导致的网络资源利用低问题,提出一种基于深度强化学习的网络切片资源分配策略。该策略运用深度强化学习优化网络切片资源分配的准入控制,通过智能体在特定时间窗口内处理资源请求,并根据不同网络切片的QoS要求及请求准入结果进行资源的动态分配。实验结果表明,所提策略相比基准算法在提高网络收益、资源利用率和接收率方面分别提升了8.33%、9.84%和8.57%。该策略能够在保证服务质量的同时提高整个网络的效率和性能。展开更多
为了提高微波光子矢量网络分析仪(MPVNA)进行脉冲测量时的动态范围,提出了一种软件门控方案,该方案利用临时闲置接收通道接收与脉冲激励产生的控制信号同源的脉冲方波,以此生成门控信号。通过这个门控信号对采集到的待测器件脉冲响应进...为了提高微波光子矢量网络分析仪(MPVNA)进行脉冲测量时的动态范围,提出了一种软件门控方案,该方案利用临时闲置接收通道接收与脉冲激励产生的控制信号同源的脉冲方波,以此生成门控信号。通过这个门控信号对采集到的待测器件脉冲响应进行控制,有效提高了信噪比和测量的动态范围。对10 GHz带通滤波器的脉冲散射参数(S参数)进行了测量,实验结果表明:在占空比为1%的脉冲激励下,应用软件门控的测量动态范围相比未应用门控时的提高了约20 d B;门控处理后测得的S11和S22参数曲线也因为信噪比的提升更加光滑和稳定。展开更多
针对工业控制网络(Industrial Control Network, ICN)远程接入场景下未经授权访问、拒绝服务攻击、欺骗攻击以及信息披露等安全问题,通过STRIDE威胁建模方法对该场景下的潜在威胁进行分析,提出一种基于动态贝叶斯博弈的接入检测框架。...针对工业控制网络(Industrial Control Network, ICN)远程接入场景下未经授权访问、拒绝服务攻击、欺骗攻击以及信息披露等安全问题,通过STRIDE威胁建模方法对该场景下的潜在威胁进行分析,提出一种基于动态贝叶斯博弈的接入检测框架。该方法能够将试图接入ICN的非法、恶意请求筛选出来并阻断,同时利用持续进行的多轮博弈迭代以及SDN灵活动态的特性对策略参数进行实时调整,以防止相同恶意接入源的再次访问。仿真实验结果表明,随着博弈轮数的增加,相比于现有的两类恶意接入防御方法,该框架的检测准确性提升了3%以上,假阳性比例下降了1.2%以上,检测效率提升了14.7%以上,且具有较好的鲁棒性。展开更多
基金supported by the National Postdoctoral Science Foundation of China(2014M550068)
文摘Large latency of applications will bring revenue loss to cloud infrastructure providers in the cloud data center. The existing controllers of software-defined networking architecture can fetch and process traffic information in the network. Therefore, the controllers can only optimize the network latency of applications. However, the serving latency of applications is also an important factor in delivered user-experience for arrival requests. Unintelligent request routing will cause large serving latency if arrival requests are allocated to overloaded virtual machines. To deal with the request routing problem, this paper proposes the workload-aware software-defined networking controller architecture. Then, request routing algorithms are proposed to minimize the total round trip time for every type of request by considering the congestion in the network and the workload in virtual machines（VMs）. This paper finally provides the evaluation of the proposed algorithms in a simulated prototype. The simulation results show that the proposed methodology is efficient compared with the existing approaches.
基金supported by the National Natural Science Foundation of China(6102100161133015+4 种基金61171065)the National Natural Science Foundation of China(973 Program)(2013CB329001)the National High Technology ResearchDevelopment Program(863 Program)(2013AA0106052013AA013500)
文摘Over the past few decades, the world has witnessed a rapid growth in mobile and wireless networks（MWNs） which significantly change human life. However, proliferating mobile demands lead to several intractable challenges that MWN has to face. Software-defined network is expected as a promising way for future network and has captured growing attention. Network virtualization is an essential feature in software-defined wireless network（SDWN）, and it brings two new entities, physical networks and virtual networks. Accordingly, efficiently assigning spectrum resource to virtual networks is one of the fundamental problems in SDWN. Directly orienting towards the spectrum resource allocation problem, firstly, the fluctuation features of virtual network requirements in SDWN are researched, and the opportunistic spectrum sharing method is introduced to SDWN. Then, the problem is proved as NP-hardness. After that, a dynamic programming and graph theory based spectrum sharing algorithm is proposed.Simulations demonstrate that the opportunistic spectrum sharing method conspicuously improves the system performance up to around 20%–30% in SDWN, and the proposed algorithm achieves more efficient performance.
文摘针对传统的IP欺骗攻击缓解方法存在运算开销大、缺乏灵活性等问题,提出了一种基于动态限制策略的软件定义网络(software defined network,SDN)中IP欺骗攻击缓解方法。首先,利用Packet-In消息中三元组信息回溯攻击路径,定位IP欺骗攻击源头主机;然后,由控制器制定动态限制策略对连接攻击源头主机的交换机端口的新流转发功能进行限制,待限制期满再恢复其转发新流的功能,限制期的大小随着被检测为攻击源的次数而增长。研究结果表明:这种动态的限制策略可阻隔攻击流进入SDN网络,从而有效避免SDN交换机、控制器以及链路过载;由于在限制期间无需再对这些限制的交换机端口进行实时监测,该方法在应对长时攻击时较传统方法具有更高的缓解效率和更少的资源消耗。
文摘面向开源项目推荐开发人员对开源生态建设具有重要意义。区别于传统软件开发,开源领域的开发者、项目、组织及相互关系体现了开放式协作项目的特点,而它们蕴含的语义有助于精准推荐开源项目的开发者。因此,提出一种基于协作贡献网络(CCN)的开发者推荐(DRCCN)方法。首先,利用开源软件(OSS)开发者、OSS项目、OSS组织之间的贡献关系构建CCN;其次,基于CCN构建一个3层深度的异构GraphSAGE(Graph SAmple and aggreGatE)图神经网络(GNN)模型,预测开发者节点和开源项目节点之间的链接,从而产生相应的嵌入对;最后,根据预测结果,采用K最近邻(KNN)算法完成开发者推荐。在GitHub数据集上训练和测试模型的实验结果表明,相较于序列推荐的对比学习模型CL4SRec(Contrastive Learning for Sequential Recommendation),DRCCN在精确率、召回率和F1值这3个指标上分别提升了约10.7%、2.6%和4.2%。因此,所提模型可以为开源社区项目的开发者推荐提供重要的参考依据。
文摘针对工业物联网中业务需求多样性和服务质量(Quality of Service,QoS)要求差异性导致的网络资源利用低问题,提出一种基于深度强化学习的网络切片资源分配策略。该策略运用深度强化学习优化网络切片资源分配的准入控制,通过智能体在特定时间窗口内处理资源请求,并根据不同网络切片的QoS要求及请求准入结果进行资源的动态分配。实验结果表明,所提策略相比基准算法在提高网络收益、资源利用率和接收率方面分别提升了8.33%、9.84%和8.57%。该策略能够在保证服务质量的同时提高整个网络的效率和性能。
文摘为了提高微波光子矢量网络分析仪(MPVNA)进行脉冲测量时的动态范围,提出了一种软件门控方案,该方案利用临时闲置接收通道接收与脉冲激励产生的控制信号同源的脉冲方波,以此生成门控信号。通过这个门控信号对采集到的待测器件脉冲响应进行控制,有效提高了信噪比和测量的动态范围。对10 GHz带通滤波器的脉冲散射参数(S参数)进行了测量,实验结果表明:在占空比为1%的脉冲激励下,应用软件门控的测量动态范围相比未应用门控时的提高了约20 d B;门控处理后测得的S11和S22参数曲线也因为信噪比的提升更加光滑和稳定。
文摘针对工业控制网络(Industrial Control Network, ICN)远程接入场景下未经授权访问、拒绝服务攻击、欺骗攻击以及信息披露等安全问题,通过STRIDE威胁建模方法对该场景下的潜在威胁进行分析,提出一种基于动态贝叶斯博弈的接入检测框架。该方法能够将试图接入ICN的非法、恶意请求筛选出来并阻断,同时利用持续进行的多轮博弈迭代以及SDN灵活动态的特性对策略参数进行实时调整,以防止相同恶意接入源的再次访问。仿真实验结果表明,随着博弈轮数的增加,相比于现有的两类恶意接入防御方法,该框架的检测准确性提升了3%以上,假阳性比例下降了1.2%以上,检测效率提升了14.7%以上,且具有较好的鲁棒性。
