A Computer Virus - Free Essay Example

Sample details Pages: 9 Words: 2847 Downloads: 1 Date added: 2017/09/25 Category Advertising Essay Type Argumentative essay Tags: Computer Essay Did you like this example? A computer virus is a computer program that can copy itself[1] and infect a computer. The term virus is also commonly but erroneously used to refer to other types of malware, adware, and spyware programs that do not have the reproductive ability. A true virus can only spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disk, CD, DVD, or USB drive. Viruses can increase their chances of spreading to other computers by infecting files on a network file system or a file system that is accessed by another computer. [2][3] The term computer virus is sometimes used as a catch-all phrase to include all types of malware, adware, and spyware programs that do not have the reproductive ability. Malware includes computer viruses, worms, trojans, most rootkits, spyware, dishonest adware, crimeware, and o ther malicious and unwanted software, including true viruses. Viruses are sometimes confused with computer worms and Trojan horses, which are technically different. A worm can exploit security vulnerabilities to spread itself to other computers without needing to be transferred as part of a host, and a Trojan horse is a program that appears harmless but has a hidden agenda. Worms and Trojans, like viruses, may cause harm to either a computer systems hosted data, functional performance, or networking throughput, when they are executed. Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious or go unnoticed. Infection strategies In order to replicate itself, a virus must be permitted to execute code and write to memory. For this reason, many viruses attach themselves to executable files that may be part of legitimate programs. If a user attempts to launch an infected program, the virus code may be executed simultaneously. Viruses can be divided into two types based on their behavior when they are executed. Nonresident viruses immediately search for other hosts that can be infected, infect those targets, and finally transfer control to the application program they infected. Resident viruses do not search for hosts when they are started. Instead, a resident virus loads itself into memory on execution and transfers control to the host program. The virus stays active in the background and infects new hosts when those files are accessed by other programs or the operating system itself. [edit] Nonresident viruses Nonresident viruses can be thought of as consisting of a finder module and a replication module. The finder module is responsible for finding new files to infect. For each new executable file the finder module encounters, it calls the replication module to infect that file. [edit] Resident viruses Resident viruses contain a replication module that is similar to the one that is employed by nonresident v iruses. This module, however, is not called by a finder module. The virus loads the replication module into memory when it is executed instead and ensures that this module is executed each time the operating system is called to perform a certain operation. The replication module can be called, for example, each time the operating system executes a file. In this case the virus infects every suitable program that is executed on the computer. Resident viruses are sometimes subdivided into a category of fast infectors and a category of slow infectors. Fast infectors are designed to infect as many files as possible. A fast infector, for instance, can infect every potential host file that is accessed. This poses a special problem when using anti-virus software, since a virus scanner will access every potential host file on a computer when it performs a system-wide scan. If the virus scanner fails to notice that such a virus is present in memory the virus can piggy-back on the virus scanner and in this way infect all files that are scanned. Fast infectors rely on their fast infection rate to spread. The disadvantage of this method is that infecting many files may make detection more likely, because the virus may slow down a computer or perform many suspicious actions that can be noticed by anti-virus software. Slow infectors, on the other hand, are designed to infect hosts infrequently. Some slow infectors, for instance, only infect files when they are copied. Slow infectors are designed to avoid detection by limiting their actions: they are less likely to slow down a computer noticeably and will, at most, infrequently trigger anti-virus software that detects suspicious behavior by programs. The slow infector approach, however, does not seem very successful. Stealth Some viruses try to trick antivirus software by intercepting its requests to the operating system. A virus can hide itself by intercepting the antivirus software’s request to read the f ile and passing the request to the virus, instead of the OS. The virus can then return an uninfected version of the file to the antivirus software, so that it seems that the file is clean. Modern antivirus software employs various techniques to counter stealth mechanisms of viruses. The only completely reliable method to avoid stealth is to boot from a medium that is known to be clean Spyware is a type of malware that is installed on computers and collects little bits information at a time about users without their knowledge. The presence of spyware is typically hidden from the user, and can be difficult to detect. Typically, spyware is secretly installed on the users personal computer. Sometimes, however, spywares such as keyloggers are installed by the owner of a shared, corporate, or public computer on purpose in order to secretly monitor other users. While the term spyware suggests that software that secretly monitors the users computing, the functions of spyware extend we ll beyond simple monitoring. Spyware programs can collect various types of personal information, such as Internet surfing habits and sites that have been visited, but can also interfere with user control of the computer in other ways, such as installing additional software and redirecting Web browser activity. Spyware is known to change computer settings, resulting in slow connection speeds, different home pages, and/or loss of Internet or functionality of other programs. In an attempt to increase the understanding of spyware, a more formal classification of its included software types is captured under the term privacy-invasive software. In response to the emergence of spyware, a small industry has sprung up dealing in anti-spyware software. Running anti-spyware software has become a widely recognized element of computer security practices for computers, especially those running Microsoft Windows. A number of jurisdictions have passed anti-spyware laws, which usually target any software that is surreptitiously installed to control a users computer. The US Federal Trade Commission has placed on the Internet a page of advice to consumers about how to lower the risk of spyware infection, including a list of dos and donts. Routes of infection [pic] [pic] Malicious websites attempt to install spyware on readers computers. Spyware does not directly spread in the manner of a computer virus or worm: generally, an infected system does not attempt to transmit the infection to other computers. Instead, spyware gets on a system through deception of the user or through exploitation of software vulnerabilities. Most spyware is installed without users knowledge. Since they tend not to install software if they know that it will disrupt their working environment and compromise their privacy, spyware deceives users, either by piggybacking on a piece of desirable software such as Kazaa, or by tricking them into installing it (the Trojan horse method). Some rogue spywa re programs masquerade as security software. The distributor of spyware usually presents the program as a useful utility—for instance as a Web accelerator or as a helpful software agent. Users download and install the software without immediately suspecting that it could cause harm. For example, Bonzi Buddy, a program bundled with spyware[9] and targeted at children, claims that: He will explore the Internet with you as your very own friend and sidekick! He can talk, walk, joke, browse, search, e-mail, and download like no other friend youve ever had! He even has the ability to compare prices on the products you love and help you save money! Best of all, hes FREE! [10] Spyware can also come bundled with other software. The user downloads a program and installs it, and the installer additionally installs the spyware. Although the desirable software itself may do no harm, the bundled spyware does. In some cases, spyware authors have paid shareware authors to bundle spywar e with their software. In other cases, spyware authors have repackaged desirable freeware with installers that slipstream spyware. Some spyware authors infect a system through security holes in the Web browser or in other software. When the user navigates to a Web page controlled by the spyware author, the page contains code which attacks the browser and forces the download and installation of spyware. The spyware author would also have some extensive knowledge of commercially-available anti-virus and firewall software. This has become known as a drive-by download, which leaves the user a hapless bystander to the attack. Common browser exploits target security vulnerabilities in Internet Explorer and in the Sun Microsystems Java runtime. The installation of spyware frequently involves Internet Explorer. Its popularity and history of security issues have made it the most frequent target. Its deep integration with the Windows environment and scriptability make it an obvious poin t of attack into Windows. Internet Explorer also serves as a point of attachment for spyware in the form of Browser Helper Objects, which modify the browsers behavior to add toolbars or to redirect traffic. In a few cases, a worm or virus has delivered a spyware payload. Some attackers used the Spybot worm to install spyware that put pornographic pop-ups on the infected systems screen. [11] By directing traffic to ads set up to channel funds to the spyware authors, they profit personally. Examples of spyware †¢ CoolWebSearch, a group of programs, takes advantage of Internet Explorer vulnerabilities. The package directs traffic to advertisements on Web sites including coolwebsearch. com. It displays pop-up ads, rewrites search engine results, and alters the infected computers hosts file to direct DNS lookups to these sites. [30] †¢ Internet Optimizer, also known as DyFuCa, redirects Internet Explorer error pages to advertising. When users follow a broken link or enter an erroneous URL, they see a page of advertisements. However, because password-protected Web sites (HTTP Basic authentication) use the same mechanism as HTTP errors, Internet Optimizer makes it impossible for the user to access password-protected sites. [31] †¢ HuntBar, aka WinTools or Adware. Websearch, was installed by an ActiveX drive-by download at affiliate Web sites, or by advertisements displayed by other spyware programs—an example of how spyware can install more spyware. These programs add toolbars to IE, track aggregate browsing behavior, redirect affiliate references, and display advertisements Computer worm A computer worm is a self-replicating computer program. It uses a network to send copies of itself to other nodes (computers on the network) and it may do so without any user intervention. This is due to the poor security the computers infected have. Unlike a virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted compute Worms with good intent Beginning with the very first research into worms at Xerox PARC, there have been attempts to create useful worms. The Nachi family of worms, for example, tried to download and install patches from Microsofts website to fix vulnerabilities in the host system – by exploiting those same vulnerabilities. In practice, although this may have made these systems more secure, it generated considerable network traffic, rebooted the machine in the course of patching it, and did its work without the consent of the computers owner or user. Some worms, such as XSS worms, have been written for research to determine the factors of how worms spread, such as social activity and change in user behavior, while other worms are little more than a prank, such as one that sends the popular image macro of an owl with the phrase O RLY? to a print queue in the infected computer. Most security experts regard all worms as malware, whatever their payload or their writers intentions. [edit] Protecting against dangerous computer worms Worms spread by exploiting vulnerabilities in operating systems. All vendors upply regular security updates[6] (see Patch Tuesday), and if these are installed to a machine then the majority of worms are unable to spread to it. If a vendor acknowledges a vulnerability, but has yet to release a security update to patch it, a zero day exploit is possible. However, these are relatively rare. Users need to be wary of opening unexpected email,[7] and should not run attached files or programs, or visit web sites that are linked to such emails. However, as with the ILOVEYOU worm, and with the increased growth and efficiency of phishing attacks, it remains possible to trick the end-user into running a malicious code. Anti-virus and anti-spyware software are helpful, but must be kept up-to-date with new pattern files at least every few days. The use of a firewall is also recommended. In the April-June, 2008, issue of IEEE Transactions on Dependable and Secure Computing, computer scientists describe a potential new way to combat internet worms. The researchers discovered how to contain the kind of worm that scans the Internet randomly, looking for vulnerable hosts to infect. They found that the key is for software to monitor the number of scans that machines on a network sends out. When a machine starts sending out too many scans, it is a sign that it has been infected, allowing administrators to take it off line and check it for viruses A Trojan horse (sometimes shortened to trojan[n 1]), is non-self-replicating malware that appears to perform a desirable function for the user but instead facilitates unauthorized access to the users computer system. The term is derived from the Trojan Horse story in Greek mythology. Purpose and operation Trojan horses are designed to a llow a hacker remote access to a target computer system. Once a Trojan horse has been installed on a target computer system, it is possible for a hacker to access it remotely and perform various operations. The operations that a hacker can perform are limited by user privileges on the target computer system and the design of the Trojan horse. Operations that could be performed by a hacker on a target computer system include: †¢ Use of the machine as part of a botnet (i. e. to perform spamming or to perform Distributed Denial-of-service (DDoS) attacks) †¢ Data theft (e. g. passwords, credit card information, etc. ) †¢ Installation of software (including other malware) Downloading or uploading of files †¢ Modification or deletion of files †¢ Keystroke logging †¢ Viewing the users screen †¢ Wasting computer storage space Trojan horses require interaction with a hacker to fulfill their purpose, though the hacker need not be the individual responsibl e for distributing the Trojan horse. In fact, it is possible for hackers to scan computers on a network using a port scanner in the hope of finding one with a Trojan horse installed, that the hacker can then use to control the target computer. [1] A trojan differs from a virus in that only a file specifically designed to carry it can do so. edit] Installation and distribution Trojan horses can be installed through the following methods: †¢ Software downloads (i. e. a Trojan horse included as part of a software application downloaded from a file sharing network) †¢ Websites containing executable content (i. e. a Trojan horse in the form of an ActiveX control) †¢ Email attachments †¢ Application exploits (i. e. flaws in a web browser, media player, messaging client, or other software that can be exploited to allow installation of a Trojan horse) Also, there have been reports of compilers that are themselves Trojan horses. citation needed] While compiling code to ex ecutable form, they include code that causes the output executable to become a Trojan horse. [edit] Removal Antivirus software is designed to detect and delete Trojan horses, as well as preventing them from ever being installed. Although it is possible to remove a Trojan horse manually, it requires a full understanding of how that particular Trojan horse operates. In addition, if a Trojan horse has possibly been used by a hacker to access a computer system, it will be difficult to know what damage has been done and what other problems have been introduced. In situations where the security of the computer system is critical, it is advisable to simply erase all data from the hard disk and reinstall the operating system and required software. [edit] Current use Due to the growing popularity of botnets among hackers, Trojan horses are becoming more common. According to a survey conducted by BitDefender from January to June 2009, Trojan-type malware is on the rise, accounting for 83-p ercent of the global malware detected in the wild Don’t waste time! Our writers will create an original "A Computer Virus" essay for you Create order

Essay about Women´s Right The Pill and Plan B - 663 Words

Does History Repeat Itself? Since the begging of time, women have always been judge harshly and have had certain standards and requirements held against them, that are presented to the community as expectable behavior for women. Women have struggled for independence and rights throughout history and currently in some places in the world; where women are limited to certain activities, political and religious beliefs. â€Å"The pill† and plan b which are oral contraception pills or also known as birth control, contributed immensely on the dramatic change of the social and sexual landscape in the United Stated and other counties in the world. It forever changed the fate women where always protrude to carry out thought their lives and certainly†¦show more content†¦It allowed them to expand their future, pursue a higher education and carrier. Women where no longer forced into motherhood but could now have the choice to shape their own lives and decide when and how many k ids they want. Plan B is similar to the Birth control, but instead is an emergency contraception used after unprotected sex or after contraception has failed. Plan B was approved by the FDA in 1999 and unlike birth control in the 1960’s there where stronger age restrictions on the drug, but soon requirements changed for availability to teen age girl. In our society today many girls are being exposed to sexual activity at an early age some acts sadly being of sexual abuse and rape. Plan B is a form to avoided unwanted pregnancies and abortions. I believe women everywhere should have access to a form of birth control or contraception of their choose but unfortunately it seems to be effecting our communities and societies morals. The rate of teen pregnancies rises and I believe it’s the lack of information given to women. Most teens now believe its okay to be sexually active at an early age without facing any consequences in the future. They believe birth control and plan b is an easy way out but in reality it is not like that, these drugs cannot protect you form sexually transmitted diseases and are not always effective. As our society changes and our older beliefs and morals held to womenShow MoreRelatedThe Plan B Pill1608 Words   |  6 PagesAs attested by the 1994 International Conference on Population and Development in Cairo, women have the right to control the number and timing of their pregnancies. In order to exercise this right, women throughout the world need access to the different types of contraceptives, as well as to safe abortion services. While most contraceptives are used as preventative measures prior to or during intercourse, some methods can be used within a short time after unprotected intercourse or failed use ofRead More Murder for Hire Essays1571 Words   |  7 Pagesexclai m, â€Å"Abortion is Murder†, â€Å"Right to Life†, and â€Å"Pro-Life.† The March for Life protest attracts approximately one quarter of a million people from across the country annually to demonstrate their disdain for abortion. Ever since the Supreme Court ruling on Roe v. Wade in 1973, Americans and lawmakers alike remain in constant dispute over the moral and legal issues of early pregnancy termination. Those opposed to abortion strongly believe that abortion negates the Right to Life, and they considerRead MoreThe Abortion Shouldn t Be Banned919 Words   |  4 Pagesyet it is completely legal. Anyone in the general public can receive a late term abortion which can be carried out up to twenty-four weeks, that is six months into a pregnancy. The article â€Å"Late Term Abortion Shouldn’t be Banned† by the Abortions Rights Coalition of Canada, supports and commends the idea of late term abortion. They state that late term abortion are only used when medically necessary. There are multiple ways to prevent pregnancy that can eliminate the need for abortions. The processRead MoreEffects Of Birth Control On Children1719 Words   |  7 Pagesconditions. Birth control may also cause women to encounter side effects like nausea, headaches, weight gain or loss, or mood swings. Despite these side effects, birth control is a very effective and beneficial drug that is used by countless women worldwide. Birth control, also named contraceptive, is a drug widely used to prevent pregnancy and other different medical issues within the female body. It uses the hormones estrogen and progestin to, â€Å"prevent a woman s ovary from releasing an egg during herRead MoreTeen Pregnancy And Teenage Pregnancy1456 Words   |  6 Pageshealth problems, experience failure in school or come into contact with the criminal justice system (Delaying Parenthood). Some women are forced to spend thousands of dollars a year on child care. Some others might have to stay at home and put five years of their lives on hold because there are no other affordable options. In five years, one could complete a bachelor s degree, climb a few rungs up the corporate ladder, or save up enough money to put a down payment on a new house (Gonzalez). TheRead MoreMandated Coverage For Birth Control On Health Insurance Plans957 Words   |  4 Pagesrestrictions are implemented on reproductive care. In 2014 there was a heated debate on whether there should be a mandated coverage for birth control on health insurance plans. According to a survey by the University of Michigan Health System, 69% of ad ults in the United States support this requirement in health insurance plans and the people who oppose this requirement is less than 10%. There have been other laws made by states recently that are affecting birth control and abortions. For exampleRead MoreAbortion : Women s Private Issues892 Words   |  4 PagesI. Introduction. When it comes to contraception and the right to an abortion, one would think these are women’s private issues because pregnancy takes place in a woman’s body. It is an intensive process of holding another living creature in her system for nine months, which would mean that the woman would have to stop her other duties in order to take care of herself and this being. Her schooling, her job, and anything else in her life. As such, it is her choice whether she wants to, or even hasRead MoreAbortion : An Incorrect Decision1592 Words   |  7 Pageshas become common in the United States, as well as other places. In 2014, 977,000 abortions occurred in the United States alone. Although this number has decreased since 2011 when the number was 1.06 million abortions, it is still too high (U.S.). Women are getting abortions without considering the very real aspect that they are taking a human life, endangering themselves in the process, and that there are various other options. Human life begins at the moment of conception. People willRead MoreThe Case Of Roe V. Wade1455 Words   |  6 Pageswould change women’s rights for years to come. This controversial case made it legal to have an abortion, which made it safer for women around the country. In 1972, a year before Roe v. Wade, there were approximately 587,000 illegal abortions performed (Roe v. Wade). These abortions were highly dangerous because they lacked medical equipment and a trained professional. In some instances, the mother could even die from the procedure. As a feminist, I believe women should have the right to their own bodyRead MoreBirth Control : A Controversial Topic Since The 1960 S1718 Words   |  7 Pagescontroversial topic since the 1960’s, when the pill arose on the scene and gained popularity. Men and women of certain religious faiths have sought to prevent other women from using birth control. However, most women want to be able to choose when the time is right for them to have a child. This is why birth control is essential, because it allows women and couples in general the freedom to choose and plan their families. In many cases the need to control women by controlling their access to birth

A Character Sketch of Rudolph Steiner (the Green Door by O’Henry) Free Essays

Rudolph Steiner belongs to the middle class of American society of the beginning of the 20th century. He is a piano salesman, a commonplace citizen on the one hand, but on the other hand he is (as the author characterizes him) â€Å"a true adventurer; few were the evenings on which he didn’t go forth from his hall bedchamber in search of the unexpected†. No matter where he goes, he tries to find an adventure in every thing possible. We will write a custom essay sample on A Character Sketch of Rudolph Steiner (the Green Door by O’Henry) or any similar topic only for you Order Now His adventurous spirit has already led him â€Å"into strange paths† several times, but he still retains it. This time, having received a card with the inscription â€Å"Green Door† from a dispenser in the street, he undertakes another evening journey. Rudolph Steiner is a commonplace American and not an American at the same time. He lives here but he is quite different from the capitalist majority. O’Henry characterizes Rudolph indirectly through his speech: †This is ridiculous to go without eatingI’m coming back tomorrow to see how you are getting along – you can’t get rid of me so easily†. This difference was (in those days) and is vitally important nowadays, Rudolph is deeply humane, despite the unspoken law of the society (as consequences of the so-called â€Å"social darvinism† – the fittest survive); he treats poor people the same way as all others and the financial state of a person he deals with is of no difference for him. We can draw this conclusion from his conduct towards the girl: he understands not only her helplessness, but spends his (probably all his) money to support her , to take her out of trouble, showing his philanthropic nature. Rudolph is awarded: the girl turns out not to be of the kind he thought before. He says: â€Å"All the same, I believe it was the hand of Fate that doped out the way for me to find her†. Rudolph Steiner is a character to draw people people’s attention to an acute problem of the society, to the disparaging treatment of the poor. The general outline of the story makes some critics think that it’s just for entertainment, like many others available on sale†, but it’s a one to make us think thanks to the character of Rudolph Steiner, a favourable exception among the majority. How to cite A Character Sketch of Rudolph Steiner (the Green Door by O’Henry), Papers

Founding Fathers of the USA Essay Example For Students

Founding Fathers of the USA Essay There are many people who can be considered the indirectfounding fathers of The United States. Such people are TheChristian Crusaders, Marco Polo, Cortez, Pizarro, andMartin Luther. The Crusades were a series of holy warsfought to win the holy land of Christianity from those whofollow Mohammed. Even though these wars failed in therespect of winning the land back, they did triumph in anotheraspect. The crusaders introduced a lifestyle to the Europeansin the Holy Land that was more appealing than they knewbefore. Following the wars the Europeans returned and theycreated a market to deliver the desirable goods they cameaccustomed to in the Holy Land. This was one reason forthe beginning of exploration, and ultimately led to thediscovery of America. Marco Polo was a great explorer ofhis time. He wrote a manuscript on his voyage entitled, TheVoyage of Marco Polo. In this manuscript it said how theKahn of China lived in riches, used fine china, decoratedwith gold, and used spices. When the manuscript reachedthe people of Europe they realized how life could better ifthey had the materials as did the Khan. This discoveryencouraged people to find new places to find these riches. Cortez founded the city of Tenochtitlan, which was createdby the Aztecs in central Mexico. He said how the people ofthis town lived with the riches of a Khan. They city wasadvanced further than any European had seen in the NewWorld. The ruler of this land, Montezuma, lived in hugeroom filled with jewels, precious stones, silver, and anastonishing amount of gold. Soon after his arrival the Aztecsrebelled. Cortez had Indian and Spanish allies and won thebattle against the Aztecs. News of the conquest of Mexicocreated a rush of Spanish to America and led to furthersettling of the continent. Francisco Pizarro found the empireof the Incas in the Andes Mountains region. This empire, likethe Aztec Empire, was advanced and rich in gold and silver. Inca, the head of the Empire and was considered a God,was killed by Pizarro. This lessened the spirit of the Incasand made it easier for Pizarro and his men to succeed amongthem. This success, again, encouraged the Europeans tosettle their own area. One of the best known reformers,Martin Luther, can be considered a founding father of TheUnited States. Luther tried to reform the Church of England,and rid it of Catholic ways. He wrote his 95 Thesis thatattacked the ways of the church and helped to better it. Hisresentment of Rome and Catholicism helped to spread thereformation into Northern Europe. This in return created adream in adventurers like Columbus to look for a new routeto India in search for worthy goods. By avoiding Italy hediscovered America. Without Luthers ideas, Columbuswould never have the dream to find the route. Each of thesepeople can be considered the founding fathers of the UnitedStates. They all played an important role in history, and inthe making of the United S tate.