数字图书馆网络安全防御系统的构建

数字图书馆为人们的日常工作学习提高了很多专业有效的数据,它拥有巨大的数据容量,但一旦受到攻击,将造成巨大损失,给人们带来诸多不便。本文针对如何有效的构建数字图书馆网络安全防御系统这一问题进行了相关分析探讨。首先列出了几大危害网络安全的因素,再根据这些因素从加强网络技术防护、规范人文管理两方面展开研究。     

网络信息系统技术安全与防范

信息安全防范是进行全面的安全漏洞检测和分析,依据其结果制定防范措施和解决方案;正确配置防火墙、网络防病毒软件、入侵检测系统、建立安全认证系统等安全系统;完善安全管理规范和机制,切实落实安全管理制度。以增强安全防范意识,确保网络信息系统安全运转。     

浅议计算机信息安全所面临的威胁以及防范技术

伴随计算机互联网技术的普及和发展,人们在网络中得到便利的同时,也因为网络的自由和开放给我们的信息安全代理一定的威胁。本文针对网络信息安全的几个方面出发,结合现在网络信息安全的实际状况以及将来的发展趋势,有针对性的提出了信息安全所面临的威胁以及针对此威胁的一些防范措施。     

有效的IPSec安全策略管理方案*

针对IPSec协议在安全策略管理存在的问题,引入信任管理的思想,介绍了一种基于信任管理的IPSec安全策略管理方案。该方案对分布式网络中的策略可以进行统一的描述,并通过一致性证明能够实现策略的委托授权管理,这样大大提高了IPSec安全策略管理效率和IPSec的灵活性。     

2000—2014年辽宁省植被动态演变特征分析

基于MODIS － NDVI 数据,辅以线性回归法与分段线性回归法,并借助ArcGIS 软件,对辽宁 省2000—2014 年植被覆盖的动态演变过程进行分析。结果表明: ( 1) 时间上,辽宁省植被NDVI 在年 际尺度上呈现出明显的增大趋势,2005 年出现突变,多年平均NDVI 值为0. 496; 春季、夏季、秋季 以及植被生长季NDVI 突变年份分别为2006 年、2005 年、2009 年和2004 年,秋季波动变化的突变点 明显滞后; 植被生长最旺盛的季节为夏季,且集中于8 月。( 2) 空间上,辽宁省植被覆盖具有明显的 地域性差异,呈现出东部高、中西部低的分布特征; 辽宁省植被覆盖优良区与辽东山地的界限基本吻 合,植被覆盖贫乏区主要集中在朝阳市和阜新市的东北部地区。( 3) 辽宁省植被覆盖程度呈山地阴坡 高于阳坡的形态,并且植被覆盖程度最好的坡向为北偏西方向。( 4) 2000—2014 年辽宁省植被覆盖度 整体以维持现状和轻微改善为主,保持不变的区域集中于中东部地区,辽阳市与沈阳市一带有轻微退 化现象,辽西北地区改善情况较为明显。     

A genetic tango attack against the David–Prasad RFID ultra‐lightweight authentication protocol

Radio frequency identification (RFID) is a powerful technology that enables wireless information storage and control in an economical way. These properties have generated a wide range of applications in different areas. Due to economic and technological constrains, RFID devices are seriously limited, having small or even tiny computational capabilities. This issue is particularly challenging from the security point of view. Security protocols in RFID environments have to deal with strong computational limitations, and classical protocols cannot be used in this context. There have been several attempts to overcome these limitations in the form of new lightweight security protocols designed to be used in very constrained (sometimes called ultra‐lightweight) RFID environments. One of these proposals is the David–Prasad ultra‐lightweight authentication protocol. This protocol was successfully attacked using a cryptanalysis technique named Tango attack. The capacity of the attack depends on a set of boolean approximations. In this paper, we present an enhanced version of the Tango attack, named Genetic Tango attack, that uses Genetic Programming to design those approximations, easing the generation of automatic cryptanalysis and improving its power compared to a manually designed attack. Experimental results are given to illustrate the effectiveness of this new attack.     

Context matters: The structure of task goals affects accuracy in multiple-target visual search

Career visual searchers such as radiologists and airport security screeners strive to conduct accurate visual searches, but despite extensive training, errors still occur. A key difference between searches in radiology and airport security is the structure of the search task: Radiologists typically scan a certain number of medical images (fixed objective), and airport security screeners typically search X-rays for a specified time period (fixed duration). Might these structural differences affect accuracy? We compared performance on a search task administered either under constraints that approximated radiology or airport security. Some displays contained more than one target because the presence of multiple targets is an established source of errors for career searchers, and accuracy for additional targets tends to be especially sensitive to contextual conditions. Results indicate that participants searching within the fixed objective framework produced more multiple-target search errors; thus, adopting a fixed duration framework could improve accuracy for career searchers.     

Security concepts for the dynamics of autonomous vehicle networks

The secure operation of autonomous vehicle networks in the presence of adversarial observation is examined, in the context of a canonical double-integrator-network (DIN) model. Specifically, we study the ability of a sentient adversary to estimate the full network’s state, from noisy local measurements of vehicle motions. Algebraic, spectral, and graphical characterizations are provided, which indicate the critical role of the inter-vehicle communication topology and control scheme in achieving security.     

基于多混沌系统的彩色图像加密方法

为了提高彩色图像加密的安全性和加密性能,设计了一种基于多混沌系统的彩色图像加密方法.将一个彩色图像分解为R、G、B三个灰度图像,使用MD5算法动态生成加密算法的初始值,然后使用三种不同的基于混沌的加密结构对三个图像进行加密.对R图像使用Feistel结构加密,其中Feistel结构的S一盒由Logistic混沌序列和Hyperhenon混沌序列组合产生;对G图像使用由Lorenz系统产生加密序列对图像进行代替和置换操作的加密结构;对B图像使用由分段线性混沌映射产生加密序列,然后加密图像的加密结构,再把加密后的图像结合起来生成加密后的图像.理论分析和实验结果表明,该加密方法能够较为有效地保证彩色图像加密的安全性.     

基于多决策树的RFID入侵检测模型

为了能够有效对RFID系统的已知攻击和未知攻击进行检测和预警,在分析大量RFID安全协议的基础上,提出了利用构建多决策树的方法对RFID系统的入侵行为进行检测。通过分析,得到所构造出的多决策树能够发现针对RFID系统的攻击之间的关系,并且具有可扩展性和高效性,使之能够适用于各种实际的RFID系统的应用。