计算机病毒外文翻译.doc

广西工学院鹿山学院 广西工学院鹿山学院外文翻译 题 目： 计算机病毒 系 别： 计算机工程系 专业班级： 计软082班 姓 名： 周政 学 号： 20081424 指导教师： 崔亚楠 职 称： 二 一二 年 四 月 十一 日 computer viruscomputer viruses are a destructive program that can replicate itself and proliferation through the network, transmission. virus code is very small, usually attached to other documents or procedures at the end, so they can easily hide in the system. ability to self-replicating virus on the network so that it can spread infection to other documents and procedures, once the virus spread to the network very difficult to track down.in 1987, computer viruses spread in the united states, and the first computer virus small ball at the end of the year spread to our country. since then, has found a virus imported and domestic. so far, computer viruses has risen to more than 20,000 kinds; which can attack more than 90% of micro-computer.1. the characteristics of computer viruses(1) the basic characteristics of(a) infection: a computer virus as a program that can replicate itself to other normal procedures or systems of certain components, such as the disk part of the guide. this is the basic characteristic of the virus program. with the increasingly extensive network development, computer viruses can be widely disseminated through the network in a short time.(b) latent: hidden in the infected system the virus does not immediately attack; the contrary, in its pre-attack, the need for a certain period of time or have certain conditions. within the incubation period, it does not show any disruption of operations, making it difficult to find the virus and the virus can continue to spread. once a virus outbreak, it can cause serious damage.(c) can be triggered: once certain conditions, the virus began to attack. this feature can be triggered is called. take advantage of this characteristic, we can control its transmission range and frequency of attacks. conditions may trigger the virus is the default date, time, file type or frequency of the computer to start.(d) damage: the damage caused by computer viruses are a wide range of - it not only undermines the computer system, delete files, change data, but also occupied system resources, such as disruption of the machine running. its destruction of the designers attempt to show.(2) general characteristics(a) express impact: in 1984, dr. fred kordon allowed to use the unix operating system xax11 / 750 computer for virus experiments. in a number of experiments, computer paralyze the average time is 30 minutes, the shortest period of time for 5 minutes. typically, if the infected computer associated with the internet, then the virus can be transmitted in a matter of hours thousands of computers.(b) it is difficult to eliminate: on the one hand, day after day a new virus or its variants; the other hand, some virus may be eliminated in the resurgence of, for example, re-use when an infected floppy disk.(c) vector characteristics: the spread of the virus can be used as the normal vector information, thus avoiding the system we set up protective measures. in the normal operating system user, the virus stealthily control system. users may also consider him the system is running normal.(d) it is difficult to detect: the virus through a variety of ways beyond our control infection, in addition, with the illegal copying and the popularity of pirated software, virus detection more difficult.(e) to deceive the characteristics of: viruses often hide themselves to avoid being detected.2. the structure of computer virusescomputer viruses usually five components - infection fu, transmission modules, damage module, trigger module and main control module.(1) infection atinfection fu, also known as virus signatures, a number of figures or characters from the ascii coding constitute. when the normal procedure of transmission of the virus when it left in the program as a virus infection at the signature. virus infection in a program intended to, it first checks whether there is any infection site; if so, the procedure has been infected, the virus will not spread it further, and if not, on the transmission of it. the majority follow this one-time transmission of the virus. if the virus does not check the site of infection, it may happen repeatedly transmitted, the length of the program would continue to increase, this situation is rare.(2) transmission modulethis is the transmission module boarding procedures. it completed three tasks: search executable file or document coverage, to check whether the document has infected fu, transmitted it - if not found to be infected with fu, on the person boarding procedures writing virus code.(3) damage moduleit is responsible for the designers of the destruction in accordance with the virus code in an attempt to undermine the implementation of mission, including delete files, delete data, formatted floppy disk and hard disk, reducing the efficiency and reduce the use of computer space.(4) trigger moduleits mission is to check whether the trigger conditions (for example, the date, time, resources, and transmission time, interrupt call, start number, etc.). if the conditions are ripe, it return true value, and damage mediator module damage, otherwise it return false value.(5) the main control moduleits control of the four modules. in addition, it has procedures to ensure that the infected can continue to work correctly, the accident would not crash happened.3. computer virus classification(1) by the parasitic categoryby parasitic, computer viruses can be divided into lead-virus, file virus and mixed virus. * boot virus: parasites in the disk guide means those parts of a computer virus. it is a common virus, the use of computer systems do not usually check the guide part of the content is correct weaknesses, and retained in memory and monitor system operation, one has the opportunity to infection and destruction. according to the location of parasites in the disk, it can further be divided into the master boot record boot record viruses and paragraph virus. the former master boot hard drive transmission parts, such as marijuana virus, 2708 virus, porch virus; record paragraph of transmission of the virus commonly used hard drive record paragraphs, such as small ball virus, girl virus.(2) by the consequences of classificationfrom the consequences of watch, computer viruses can be divided into benign viruses and vicious virus. benign virus would destroy data or programs, but it will not make computer systems paralyzed. initiator of the virus are most mischievous hackers - they created the virus is not in order to undermine the system, but in order to show off their technical capacity; some hackers use these viruses to disseminate their political thought and ideas, such as small ball virus and ambulance car virus. vicious virus would destroy data and systems, resulting in paralysis of the entire computer, such as the chi virus, porch virus. once the virus attack, the consequences will be irreparable.it should be noted that dangerous are a common feature of computer viruses. benign viruses are not dangerous, but the risk of the consequences of relatively light. virtuous is a relative concept. in fact, all computer viruses are malignant.4. computer virus detection, elimination and prevention(1) computer virus detectionat present, caused by computer viruses in software and hardware failures cause increasingly serious damage. most failures happen with the virus. in the computer by the computer virus infection or virus attack, there will be anomalies. through the observation of these anomalies, you can determine the computer whether the initial infection of computer viruses. the following anomalies may indicate that the computer virus has infected your computer:* procedures for loading longer than usual.* the size of executable files change.* visit to the hard drive longer.* print slowly.* screen some strange characters and unusual display.* some system failures, such as the system can not access the hard disk.* the actual memory size significantly smaller.* abnormal death.* program and data mysteriously disappeared.* abnormal sound from loudspeakers.(2) the elimination of computer viruses(a) the principle of the elimination of the virus* prior to the elimination of the virus, backup all important data to prevent loss.* use clean (no virus) the system disk to guide the computer, thereby ensuring that the virus program to kill virus-free environment in the run, otherwise the virus will again have disinfection of infected documents.* to retain the guidance system of the order in the system will not boot recovery.* be careful when operating. repeatedly to check read and write data until the beginning of the operation did not find any errors.(b) how to eliminate computer viruses?at present, in order to eliminate computer viruses, artificial methods or tools can be used; but most use the latter method.if it is found that part of the hard disk boot record has been destroyed, can be used to restore the correct boot record it. if any documents are found to be infected, use the normal document covering the same name it, or delete the file. all of these are artificial.(c) the prevention of computer virusesfirst, we must rely on the law and the fight against computer viruses. law must be clear that the deliberate creation and dissemination of computer viruses is a crime. china has promulgated and implemented for the protection of information system security requirements. this reflects the work of computer security has embarked on the legal system. each person should attach importance to computer security issues. secondly, we need to develop regulations and the implementation of management measures will be prevention as the fight against computer viruses transplantation major measures. specific measures include the following:* the use of an important sector of the computer should be special plane, with external isolation;* do not use a source of unknown or unclear whether the infected floppy disks and cd-rom;* used with caution and common utility software;* contains important data in the floppy disk set write-protected. writing when the person, the temporary elimination of protection, write protection, after re-setting.* regular inspection of computer systems and regular backup procedures;* use the hard disk boot. if you use a floppy disk, first of all virus-free floppy disk verification;* do not hesitate to lend to others floppy disk. if you have to lend, should first make a backup disk, and also to re-format the disk;* when buying a new cd-rom or floppy disk, use the former should first check the virus; * upgrade to the computer equipped with the latest anti-virus software;* if possible, install on your computer anti-virus software;* strictly forbidden to play games on the computer, because the virus often parasitic in the game software;* internet-linked computer online or offline should have anti-virus system (firewall);* when you discover new viruses, timely reporting to the local computer security departments.anti-virus software tools can automatically prevent, detect and eliminate computer viruses. use anti-virus tool is a speedy, efficient and accurate method. at present, there are many excellentanti-virus software tools, such as the kill 2000, kv300, av95, etc. and rising. use anti-virus software should upgrade to the latest version, because new viruses are emerging. computer viruses and anti-struggle between a computer virus will continue. 计算机病毒计算机病毒是带有破坏性的程序，它能够自我复制并通过网络扩散、传染。病毒代码很小，通常附在其他文件或程序末尾，因此它们很容易隐藏在系统内部。病毒的自我复制能力使其在网络上传播时能够传染给其他文件和程序，病毒一旦扩散到网络上就非常难以追踪了。1987年，计算机病毒在美国四处蔓延，而且第一种计算机病毒“小球”在当年年底传播到我国。从那以后，已经发现进口和国内的病毒。迄今为止，计算机病毒已经增加到20,000多种；其中90以上能攻击微型计算机。1.计算机病毒的特征 （1）基本特征(a)传染：计算机病毒作为一个程序，能自我复制到其他正常程序或者系统的某些部件上，例如磁盘的引导部分。这是病毒程序的基本特征。随着网络日益广泛发展，计算机病毒能够在短时间内通过网络广泛传播。(b)潜伏：隐藏在受感染系统内的病毒并不立即发作；相反，在它发作前，需要一定时间或具备某些条件。在潜伏期内，它并不表现出任何扰乱行动，因此很难发现病毒并且病毒能够继续传播。一旦病毒发作，它能造成严重破坏。(c)可触发性：一旦具备某些条件，病毒便开始攻击。这一特征称作可触发性。利用这一特征，我们能控制其传染范围和攻击频率。触发病毒的条件可能是预设的日期、时间、文件种类或计算机启动次数等。(d)破坏：计算机病毒造成的破坏是广泛的它不仅破坏计算机系统、删除文件、更改数据等，而且还能占用系统资源、扰乱机器运行等。其破坏表现出设计者的企图。(2)一般特征(a)快速影响：1984年，弗雷德科登博士获准在使用unix操作系统的xax11 / 750计算机上进行病毒实验。在多次实验中，计算机瘫痪的平均时间为30分钟，最短的时间为5分钟。通常，如果受传染的微机与因特网相联，则病毒在几小时内能传染数千台计算机。(b)难以消除：一方面，日复一日出现新病毒或其变种；另一方面，一些病毒在被消除后可能死灰复燃，例如在重新使用受感染的软盘时。(c)载体特征：病毒能够作为载体传播正常信息，因而避开我们在系统中设置的保护措施。在用户正常操作系统时，病毒偷偷控制系统。用户可能还认为他的系统运行正常。(d)难以探测：病毒通过各种超出我们控制的方式传染，此外，随着非法复制和盗版软件大行其道，病毒探测变得更加困难。(e)欺骗特征：病毒往往隐藏自己，避免被探测到。2计算机病毒的结构计算机病毒通常由五部分构成感染符、传染模块、破坏模块、触发模块和主要控制模块。(1)感染符感染符也称作病毒签名，由若干数字或字符的ascii编码构成。当病毒传染正常程序时，它在程序上留下病毒签名作为感染符。在病毒打算传染一个程序时，它首先检查是否有感染符；如果有，程序就已经被感染，病毒不会进一步传染它，如果没有，就传染它。多数病毒遵循这种一次性传染。如果病毒不检查感染符，则可能发生多次传染，该程序的长度将不断增加，这种情况很少见。(2)传染模块这是传染寄宿程序的模块。它完成三项任务：查找可执行的文件或被覆盖的文件，检查该文件上是否有感染符，传染它如果没有发现感染符，就在寄宿程序中写人病毒编码。(3)破坏模块它负责按照病毒设计者在破坏编码中的企图执行破坏任务，包括删除文件、删除数据、格式化软盘和硬盘、降低计算机效率和减少使用空间等。(4)触发模块其任务是检查是否具备触发条件（例如，日期、时间、资源、传染时间、中断调用、启动次数等）。如果条件成熟，它返回“真”值，并且调人破坏模块进行破坏，否则它返回“假”值。(5)主要控制模块它控制上述四个模块。此外，它还确保受传染的程序能继续正常工作，在意外情况下不会发生死机。3计算机病毒分类(1)按寄生分类按寄生，计算机病毒可分成引导病毒、文件病毒和混合病毒。引导病毒：指寄生在磁盘引导部分的那些计算机病毒。它是一种常见病毒，利用计算机系统通常不检查引导部分的内容是否正确的弱点，并且留存在内存中，监视系统运行，一有机会就传染和破坏。按寄生在磁盘的位置，它能进一步分成主引导记录病毒和段引导记录病毒。前者传染硬盘的主引导部分，例如“marijuana”病毒、“2708”病毒、“porch”病毒；段记录病毒传染硬盘上的常用段记录，例如“小球”病毒、“女孩”病毒等。(2)按后果分类