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基于国内开展信息系统安全测评的重要性和迫切性背景分析,论文首先提出了测评平台的需求和目标,然后说明了该测评平台的总体框架和逻辑结构,并对关键模块测评子系统和测评方案生成子系统模块做出了进一步设计分析,最后给出了系统平台的软件功能体系。 相似文献
43.
《Optik》2014,125(16):4446-4451
With the number of large capacity applications in core network increasing, the bandwidth requirement of optical connections in conventional Wavelength Division Multiplexing (WDM) networks keeps enhancing, so that the Orthogonal Frequency Division Multiplexing (OFDM) technology is adopted to provide higher spectrum efficiency and flexibility in the future elastic optical networks. Meanwhile, survivability in the conventional WDM optical networks has been widely studied as an important issue to ensure the service continuity. However, survivability in OFDM-based elastic optical networks is more challenging than that in conventional WDM optical networks because each fiber usually carries even more connections. Therefore, it is necessary to study the new lightpath protection algorithm in elastic optical networks. Since p-cycle protection scheme has short restoration time and simple protection switching procedure, in this paper, we study the static Survivable p-Cycle Routing and Spectrum Allocation (SC-RSA) problem with providing an Integer Linear Programming (ILP) formulation. Since RSA is a NP-hard problem, we propose a new heuristic algorithm called Elastic p-Cycle Protection (ECP) to tolerate the single-fiber link failure. For each demand, ECP scheme can compute highly-efficient p-cycles to provide protection for all of the on-cycle links and the straddling links. We also consider the load balancing and choose the proper working path for each demand. Simulation results show that the proposed ECP scheme achieves better performances than traditional single-line-rate survivable schemes. 相似文献
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本文叙述了Al-Li合金光谱分析用标准样品的制备过程和定值结果。在制备过程中采用了先进的氩气保护、新型熔剂覆盖盖技术防止锂元素的烧损,首创作了“间歇式半连续铸造法 ”、“分步调整成分法”等先进的工艺,解决了Al-Li标样铸锭不锡成形、成易偏析等技术难关;最后采用多家协作分析定值法和科学的数理统计方法对数据处理给出定值结果和不确定度。 相似文献
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Routing for shared protection in multi-domain networks is more difficult than that in single-domain networks because of the scalability requirements. We propose a novel approach for shared protection routing in multi-domain networks where the key feature is a special Topology Aggregation. In this Topology Aggregation, only some potential intra-domain paths (intra-paths for short) are selected for carrying working and backup traffic between domain border nodes. The abstraction of each intra-path to a virtual edge makes the original multi-domain network to become an aggregated network. On the aggregated network, a single-domain routing algorithm for shared protection can be applied for obtaining the complete routing solutions. The experiments show that the proposed approach is scalable. Moreover it is close to the optimal solution in single-domain networks and outperforms the previously proposed scalable solutions in multi-domain networks. 相似文献
48.
Fiber-Wireless (FiWi) access network is now becoming a promising architecture for access networks. Survivability is one of the key issues in the planning of FiWi access network because many high-rate traffic flows may be interrupted in case of a single fiber failure, which can cause a huge traffic loss. In addition, the users need ubiquitous broadband access that can be provided by FiWi access network. In this paper, we propose the protection approach called Maximum Covering Planning with Survivability (MCPS), including Integer Linear Programming (ILP) solution and heuristic solution, for the planning of survivable FiWi access network against single distribution fiber failure. The proposed approach aims at maximum coverage under the constraints of network connectivity. When a distribution fiber is broken, the interrupted Optical Network Unit (ONU) can transmit traffic to its backup ONU through the wireless paths between them. Simulation results show the network coverage of clients for different number of ONUs in different urban areas, and demonstrate the relationship between network coverage and the cost represented by the number of WiFi routers. 相似文献
49.
随着全固态中波广播发射机的大量应用,其防雷问题也愈加凸显出它的重要性。本文根据河南省许昌中波转播台发射系统的防雷现状,分析研究我台防雷工作中存在的问题和解决方法,以及实施防雷技术布控的必要性、可行性,以保障中波广播发射机的安全运行,确保安全优质播出顺利进行。 相似文献
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面对日益增大的网络安全威胁,电信运营商需要提高业务平台的安全防护能力.结合电信运营商业务平台的系统现状,在对各类业务平台进行安全分级的基础上,规范划分不同网络结构业务平台的安全域,并针对不同安全等级平台设计合理可控的安全防护策略和安全基线,使业务平台形成安全、清晰、便于管控的网络布局和系统架构. 相似文献