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991.
信息技术服务质量模型定义了信息技术服务的质量特性,包括安全性、可靠性、响应性、有形性、友好性,并对其质量特性进行分解,最终落实到便于操作、计算的评价指标上。质量评价结果可以有效地反映供方的服务水平。 相似文献
992.
介绍美国FedRAMP项目的背景和主要目标,梳理FedRAMP项目的治理实体和各利益相关方的义务、职责及相互交互,分析了FeRAMP项目的安全授权过程. 相似文献
993.
In recent years, the file-sharing applications of peer-to-peer (P2P) systems, such as Napster, Bit-Torrent (BT), Gnutella, have become very popular, with BT offering particularly high sealability and efficiency service to transmit files. But BT does not enforce the access control process, so a lot of unauthorized files are freely shared. In this paper, we proposed a digital rights management (DRM) system for BT environment to solve the serious piracy issue by using lightweight encryption methods in order to he adopted by small mobile devices in wireless environment. 相似文献
994.
995.
Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language (OWL) to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given higher level security policy and the lower level ones to evaluate the compliance for the policy refinement approach. The method is verified in the case study. The experimental results demonstrate that the proposed method evaluates the semantic similarity between policy and implementation accurately, and that the algorithm of concept similarity analysis reflects the subjective similarity judgment of policy and implementation more accurate than the other algorithms. 相似文献
996.
Wireless Mesh Networks (WMNs) are vulnerable to various security threats because of their special infrastructure and communication mode, wherein insider attacks are the most challenging issue. To address this problem and protect innocent users from malicious attacks, it is important to encourage cooperation and deter malicious behaviors. Reputation systems constitute a major category of techniques used for managing trust in distributed networks, and they are effective in characterizing and quantifying a node狆s behavior for WMNs. However, conventional layered reputation mechanisms ignore several key factors of reputation in other layers; therefore, they cannot provide optimal performance and accurate malicious node identification and isolation for WMNs. In this paper, we propose a novel dynamic reputation mechanism, SLCRM, which couples reputation systems with a cross-layer design and node-security-rating classification techniques to dynamically detect and restrict insider attacks. Simulation results sho that in terms of network throughput, packet delivery ratio, malicious nodes' identification, and success rates, SL-CRM implements security protection against insider attacks in a more dynamic, effective, and efficient manner than the subjective logic and uncertainty-based reputation model and the familiarity-based reputation model. 相似文献
997.
998.
WIFI技术是无线领域新兴的技术,它以其传输速度高、覆盖范围广的特点而日益受到人们关注。针对WIFI网络存在的诸多安全因素的困扰,文中在简要介绍了WIFI的概念、特点的基础上,较详细地分析了WIFI网络的安全机制,重点论述了WPA的核心技术、存在的安全问题。最后提出了使用WIFI网络应采取的安全防范措施。 相似文献
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1000.
张滨 《电信工程技术与标准化》2021,34(12)
5G作为数字经济发展的重要驱动力,将促进数据要素的集聚和海量增长,通过更广阔的覆盖和更稳定高效的网络连接,加速垂直行业的数字化转型。随着5G新技术的引入,5G与各个垂直行业深度融合,数据量级不断增长,同时也带来了新型数据安全风险,对5G数据安全防护提出了更高的要求。本文在分析5G数据全生命周期安全风险的基础上,深入分析5G各场景和技术领域的特有数据安全风险,提出5G数据安全整体防护方案,助力5G数据安全发展与治理。 相似文献