浅析计算机数据库入侵检测技术

在互联网时代,计算机数据在各个行业中有着广泛的应用,改变人们的工作和生活方式.计算机数据库入侵检测技术引起了人们越来越多的重视.本文将介绍计算机数据库入侵技术的相关概念和功能,并探讨目前比较流行的防范技术,指出相关技术存在的问题,并给出了优化方案.     

An Information Hiding Algorithm Based on Bitmap Resource of Portable Executable File

An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable （PE） files. This algorithm has higher security than some traditional ones because of integrating secret data and bitmap resources together. Through analyzing the principle of bitmap resources parsing in an operating system and the layer of resource data in PE files, a safe and useful solution is presented to solve two problems that bitmap resources are incorrectly analyzed and other resources data are confused in the process of data embedding. The feasibility and effectiveness of the proposed algorithm are confirmed through computer experiments.     

Study of Intrusion Detection Systems

Modern network systems have much trouble in security vulnerabilities such as buffer overflow, bugs in Microsoft Internet, sensor network routing protocol too simple, security flaws of applications, and operating systems. Moreover, wireless devices such as smart phones, personal digital assistants （PDAs）, and sensors have become economically feasible because of technological advances in wireless communication and manufacturing of small and low-cost sensors. There are typologies of vulnerabilities to be exploited in these devices. In order to improve securities, many mechanisms are adopted, including authentication, cryptography, access control, and intrusion detection systems （IDS）. In general, intrusion detection techniques can be categorized into two groups： misuse detection and anomaly detection. The misuse detection systems use patterns of weB-known attacks or weak spots of the systems to identify intrusions. The weakness of misuse detection systems is unable to detect any future （unknown） intrusion until corresponding attack signatures are intruded into the signature database. Anomaly detection methods try to determine whether the deviation is from the established normal usage patterns or not. The critical success of anomaly detection relies on the model of normal behaviors.     

Quantitation Method to the Imperceptibility of ：-Iiding-Vector in Multi-dimensional Hiding Space

Currently, few general methods have been suggested to quantitate the imperceptibility among var- ious hiding algorithms. Especially, it is a challenge to quantitate the imperceptibility of the hiding-vector, which is consisted of orthogonal hiding algorithms in the multi- dimensional hiding space. In this paper, a novel model of general imperceptibility quantitation was proposed. Ac- cording to this model, a quantitation method based on the relative entropy was designed. It is proved under this quantitation method that there exists the global maximal imperceptibility for any specified hiding-vector capacity. An optimization algorithm was proposed to approach this maximum by adjusting the allocation of secret message into each components of the hiding-vector. Experiments with VoIP and bitmap multi-dimensional hiding space validated the effectiveness of the designed quantitation method and the proposed optimization algorithm.     

网络攻防关键技术探讨

网络安全问题是所有网络用户都面临的问题,而且随着计算机网络技术的发展,网络入侵技术自动化、智能化和多样化程度越来越高,严重影响网络用户的信息安全。做好网络安全防御工作刻不容缓。本文首先对网络入侵关键技术中的信息收集技术和攻击技术进行简要介绍,再结合当前网络防御技术的现状,分析主动防御技术体系中的两个关键防御技术:入侵检测技术和入侵预测技术。     

Android平台下的安全检测软件的设计与实现

本文为了阻止Android手机恶意软件病毒的危害,分析了入侵病毒的类型,提出了一个基于Android平台的安全检测软件的设计方案,并实现了该方案。该软件基于Android的体系机构,结合Android体系自身的特点,实现了查杀病毒、检测支付环境、监听电话短信、检测流量等功能,保障了用户的安全。经过真机和模拟机测试,该软件能够有效查杀病毒、检测到潜在的病毒危害并及时采取措施,达到了设计目的。     

基于共生特性的G.729A基音调制信息隐藏的检测

提出了一种G.729A自适应码本分组基音调制信息隐藏的检测算法.对语音码流的分析发现,通过基音预测进行信息隐藏将改变相邻语音帧中基音周期估计值的共生特性.通过量化这种共生特性,并经过PCA(Principal Component Analysis,主成分分析)降维获得对隐写检测敏感的特征向量.最后基于特征向量和SVM (Support Vector Machine,支持向量机)构建隐写检测器.对不同语音样本数据集的检测表明,当语音长度在2s及以上时,检测正确率均超过96%.此检测算法是一种有效的压缩域信息隐藏检测方法.     

入侵检测中基于SVM的两级特征选择方法

针对入侵检测中的特征优化选择问题,提出基于支持向量机的两级特征选择方法。该方法将基于检测率与误报率比值的特征评测值作为特征筛选的评价指标,先采用过滤模式中的Fisher分和信息增益分别过滤噪声和无关特征,降低特征维数;再基于筛选出来的交叉特征子集,采用封装模式中的序列后向搜索算法,结合支持向量机选取最优特征子集。仿真测试结果表明,采用该方法筛选出来的特征子集具有更好的分类性能,并有效降低了系统的建模时间和测试时间。     

智能家居安防系统

智能家居安防系统是传感技术、无线电技术、模糊控制技术等多种技术为一体的综合应用,利用现代的宽带信息网络和无线电网络平台,将家电控制、家庭环境控制、家庭监视监测、家庭安全防范、家庭信息交流、家庭娱乐、小区管理和服务集为一体构成的智能系统产品,是具有较强的技术性和前瞻性的新产品。这套系统包含门磁传感器、红外广角探测器、红外幕帘探测器等。安装门磁、窗磁,防止非法入侵,管理系统可通过安装在住户室内的报警控制器得到信号从     

入侵检测系统与防火墙联动技术研究

防火墙和入侵检测系统,是网络中应用最广泛的两种网络安全产品,将防火墙和入侵检测系统整合起来,构造一个开放的网络安全平台,通过他们之间的信息联动以实现网络的整体安全防护。