防火墙技术探讨

Internet的迅速发展提高了人们工作效率，丰富了人们的生活，同时也带来了一个日益严峻的问题——网络安全。防火墙技术目前已成为一种重要的网络安全机制，本文介绍了防火墙技术的发展过程，又分析了几种不同防火墙系统的特点，最后展望了防火墙技术的发展趋势。     

基于网络处理器的防火墙设计

随着Internet的高速发展，软件防火墙成为性能瓶颈，硬件防火墙不具有通用性，而基于网络处理器的防火墙设备具有可编程的特点，并且可以实现硬件防火墙的性能。     

防火墙的原理与设计技术

本文先简要介绍了防火墙的基本知识和主要功能,介绍了一种高安全性防火墙的实例。     

防火墙技术分析

防火墙技术是实现网络安全的主要手段,文章对防火墙技术进行了分析,介绍了防火墙的种类、体系结构、功能和一些不足,最后展望了防火墙技术的发展方向。     

利用防火墙技术抵御几类攻击

介绍了路由器防火墙的概念，作用、分类、缺陷和防范可能遭受的攻击，以及几种典型安全配置方案。     

安全防火墙的设计

文章主要讨论了防火墙设计的安全策略以及国外产品的最新性能比较。     

基于网络处理器的防火墙设计

随着Internet的高速发展,软件防火墙成为性能瓶颈,硬件防火墙不具有通用性,而基于网络处理器的防火墙设备具有可编程的特点,并且可以实现硬件防火墙的性能。     

防火墙的原理与设计技术

本文先简要介绍了防火墙的基本知识和主要功能,介绍了一种高安全性防火墙的实例。     

防火墙的原理与设计技术

本先简要介绍了防火墙的基本知识和主要功能，介绍了一种高安全性防火墙的实例。     

网络安全与防火墙体系

在网络安全问题中，防火墙技术作为重要组成部分，从产生到发展，经历了技术形式上的变化。本文就基本概念和体系结构，以及应用在网络安全上的包过滤技术、代理服务技术、流过滤、防火墙标准问题作一些介绍，并提出防火墙体系的具体应用。     

A comparison of optical buffering technologies

We describe the practical and fundamental limitations of the more prominent optical buffering approaches. The architectural implementation and needs of an optical packet switch are used as a foundation for the study. We also present initial results for a buffered, all-optical, 40 Gb/s packet switch.     

滤波器技术简要回顾

开关电容滤波器技术允许使用片外或片内时钟调整滤波器截止频率,时钟频率是截止频率的倍数.这个本来非常方便的特性,却总是被这类滤波器的"采样数据"的本质弄得不方便.即这种技术总需要一个时钟,一个在纯模拟电路中的数字部分.     

DSP硬件技术综述

信号处理从数学上看就是一个运 算系统,所以不管采用什么方法,只要满足了运算要求、实现了运算结构,就可以认为是完成了系统的要求。因此,数字信号处理（ＤＳＰ）技术是实现系统的最佳选择。在信息技术应用的驱动和电子技术的支持下,近１０年来,ＤＳＰ技术的得到了迅速发展。是现代科学技术的重要基础技术,是现代电工电子理论和技术的重要组成部分和研究对象。 近１０年来,ＤＳＰ技术的发展可以分为两个方向,一个是基本理论和应用理论的发展,另一个方面是硬件技术的发展。从工程应用的角度看,硬件技术的发展是ＤＳＰ工程应用的基…     

虚拟维修技术综述

近年来,虚拟现实技术蓬勃发展,由此带来了装备维修领域的重大革新,即虚拟维修技术。在维修训练和维修性设计分析领域,虚拟维修技术的研究取得了一系列重大进展,并在实际中得到了广泛的应用,取得了巨大的经济和社会效益。为了更好地运用虚拟维修技术,文中介绍了虚拟维修的定义、功能、组成要素、实现方式、关键技术以及系统设计原理和过程,并论述了国内外虚拟维修的发展情况,展望了其在未来的发展趋势。     

A comparison of competing broadband in-home technologies

Connecting each house to a broadband access network represents an unprecedented opportunity to offer added-value services and broadband Internet access to residential users and expand the customer base beyond the corporate environment. Home networks, however, may be the last barrier to end-to-end multimedia service provisioning. Although a large number of houses have PCs, modems or multimedia network-enabled appliances, the majority are not equipped to support their interconnection, and most consumers are unwilling or cannot afford large-scale home rewiring. This paper reviews the available home-networking technologies and provides a comparison of the competing broadband in-home technologies. The focus is on technologies that do not require rewiring the home, either reusing the existing wiring or using wireless technology. The paper also discusses the residential gateway (RG) initiative, which provides a single point of convergence between the in-home and the access networks     

A review and evaluation of networking technologies

The past few years have witnessed some of the major breakthroughs in data communications technologies and services. Most notably, broadband networking (e.g., Asynchronous Transfer Mode), Client/Server Computing, and Personal Communication Systems have revolutionized the field of data communication. These new technologies will have important implications for end-users as well as network managers and administrators. This article presents a review of the new networking technologies and an evaluation of each.     

A DC-DC converter for short-channel CMOS technologies

An integrated DC-DC converter with two passive external components was designed and fabricated in an advanced, short-channel (L_eff <0.2 μm, V_dd<2 V) CMOS technology. This design was undertaken to examine the feasibility of implementing an inductive buck converter with passive components small enough to fit entirely within a packaged chip. High switching frequencies (>10 MHz) were used to minimize the size of external components, and novel circuits were used to reduce the stress on the short channel devices. Measured efficiencies for a 3.3 V to 1.65 V converter were approximately 75% for output currents from 15 to 40 mA     

车联网安全防护技术综述

车路云协同的车联网体系已经逐步上升为国家战略,车联网安全关系到行车安全、生命财产安全甚至国家安全,正日益成为行业研究热点。首先介绍了车联网技术架构与安全行业的整体状况;其次,以车联网“车-路-云”技术体系为基准,从车联网终端安全、车联网路侧安全、车联网云端安全3个层面,讨论了国内外研究现状,并分析了车联网安全防护领域的问题与挑战;最后,展望了车联网安全防护技术未来的发展与研究重点。     

A countermeasure againstDDOS attacks using active networks technologies

A Distributed Denial of Service (DDoCS) attack consumes the resources of a remote host or network by sending a massive amount ofIP packets from many distributed hosts. It is a pressing problem on the Internet as demonstrated by recent attacks on major e-commerce servers andISPs. Since the attack is distributed and the attack tools evolve at a rapid and alarming rate, an effective solution must be formulated using a distributed and adaptive approach. In this paper, we propose a countermeasure againstDDoCS attacks using a method we call Active Shaping. Our method employs the Active Networks technologies, which incorporates programmability into network nodes. The Active Networks technology enables us to deter congestion and bandwidth consumption of the backbone network caused byDDoCS attacks, and to prevent our system from dropping packets of legitimate users mistakenly. This paper introduces the concept of our method, system design and evaluates the effectiveness of our method using a prototype.     

A survey on wireless ATM technologies and standardization

Growing emphasis on multimedia traffic has underlined the importance of broadband asynchronous transfer mode (ATM) networks which are capable of supporting demanding applications such as audio/video playback, image browsing, real-time voice/video transmission and interactive data exchange in a unified manner. However, the extension of ATM from wireline to wireless creates a new set of challenging issues. ATM standards are developed based on high data rates and reliable transmission links. This is in contrast to wireless channels where bandwidth is limited and error rates are high. Furthermore, existing ATM specifications are designed primarily to provide services to fixed end-terminals with little ability to adapt to mobile connections and the highly time-varying conditions associated with wireless networks. This paper surveys the major technical and service issues related to the deployment of ATM in third-generation wireless networks. It will also cover how international standards are progressing in this important area. This revised version was published online in August 2006 with corrections to the Cover Date.