局域网中IP地址盗用的分析与防范

网络从上世纪50年代起步至今已经有60多年的发展历程。现今,无论在Internet或者Intranet的网络上,使用TCP/IP协议的每台主机必须具有独立的IP地址,有了IP地址的主机才能与网络上的其他主机进行通信。随着网络应用大力推广,网络客户急剧膨胀,由于静态IP地址分配,IP地址冲突的麻烦相继而来。IP地址冲突造成了很坏的影响。同时,IP地址的盗用行为侵害了网络正常用户权益,并且给网络安全、网络正常运行带来重大隐患。因此,研究IP地址盗用,找出有效的防范措施。本文将从IP地址盗用开始分析,分析一系列解决方案,然后再提出更进一步的解决方案。     

基于GPRS的用户IP寻址

GPRS技术的引进,把电信网络和计算机有机的连接在一起,朝未来的全IP网络平台发展.本文从GPRS用户IP地址的分配、路由管理分析,并结合铁路运输的特点着重阐述移动设备的IP寻址过程.     

网络地址转换技术及其应用

网络地址转换是指内部网络的主机要访问外部Internet网络时,具有地址转换功能的设备(路由器)将其内网IP地址转换为合法的公网IP地址进行访问外网。通过地址转换可以将内网与外网隔离开,让外网用户无法知道内网的拓扑结构,从而提高网络的安全性。通过地址转换技术实现多个用户同时使用同一个合法IP与外部Internet进行通信,有效缓解公网IP地址匮乏问题。     

全IP的有线无线一体化接入与认证技术

本文介绍了未来全IP化的网络,提出了基于IPv6协议的有线无线一体化接入和认证系统。这种接入网络可同时为有线用户和无线用户提供IP网络接入服务,能够进行认证和计费,能够支持IP漫游和移动。采用IPv6协议保证了为每个终端分配一个全局IP地址。满足未来基于IP的、端到端的通信需要。并对有线无线一体化接入和以太网接入认证技术进行了分析。     

逻辑AND在IP计算中的应用

TCP/IP是INTERNET上每台计算机之间通信共同遵循的一种通信协议,其中IP对我们来说是至关重要,IP地址能够唯一地确定internet上每台计算机所属的网络及每个用户的位置.利用逻辑AND将IP地址和子网掩码对应相与便能求出,文章详细讲述了逻辑AND在IP计算中的应用.     

一种对IP地址分配的监测管理方法和实现

采用DHCP服务器自动分配IP地址,是解决IP地址不足的有效途径.但是,即使在采用DHCP的环境中,IP地址冲突的情形仍偶有发生,因为用户仍可手动设定自己计算机的IP地址,不理会DHCP所分配的网段,这种情况在校园网络屡见不鲜.文章提出一种IP地址指派的监测机制,通过SNMP网络管理协议至路由器设备检查网络中IP地址的使用情形,并通过DHCP日志文件的分析,找出违反规定使用IP地址的计算机,解决IP地址盗用与地址冲突的问题,可以有效降低网管人员的负担.     

MAC地址和IP地址在网络中的应用

计算机网络和Internet网络中,存在着的MAC(物理地址)和IP地址,网络双方的通信必须按照地址来进行,本文详细对介绍网络中的MAC和IP地址的知识并对它们的一些典型的应用进行了阐述。     

可变IP地址用户间通信支持系统的设计与实现

可变IP地址用户间通信支持系统主要用于解析接入内部网的用户信息,实现对用户的可变IP地址的动态管理,为内部网中的用户提供信息服务,以达到支持可变IP地址用户之间进行通信的目的。本文介绍了接入内部网的用户间通信的两种方法,着重介绍了可变IP地址用户间通信支持系统的设计与实现。     

基于GPRS的用户IP寻址

GPRS技术的引进,把电信网络和计算机有机的连接在一起,朝未来的全IP网络平台发展。本文从GPRS用户IP地址的分配、路由管理分析,并结合铁路运输的特点着重阐述移动设备的IP寻址过程。     

上Internet为何要设置DNS

Internet是由成千上万的计算机通过各类网络互连设备和通讯线路连成的一个全球性的巨型网络。在这个网络中有许多计算机可以为加入Internet的其他计算机用户提供各类信息服务。为了使这些连入Internet的众多计算机能够在通信时相互识别,Internet中的每一台计算机都被分配了一个唯一的32位二进制数的数字型地址,在网络中称之为IP地址。通信时接收方的IP地址     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.