By Brayden Alexander A computer virus is malicious software designed to spread to other computers by inserting herself into legitimate programs called "guests." It can more or less seriously damage the functions of the infected computer. It can spread through any medium of exchange of digital data such as computer networks and CD-ROMs, USB keys, etc.Its name comes from an analogy with biological viruses because it has similarities in the way it is spread using the reproductive capability of the host cell. It assigns the term "computer virus" in computer and molecular biologist Leonard Adleman (Fred Cohen, Experiments with Computer Viruses, 1984). Computer viruses are not to be confused with computer worms, which are programs that can spread and replicate on their own without contaminating the host program. In a broad sense, is often used and misused the word virus to designate any form of malware.The total number of malicious programs known to be about 95 000 according to Sophos (all types of malware combined). However, the actual number of viruses in circulation would not exceed a few thousand depending on the WildList Organization, every antivirus vendor with an interest in "inflating" the number of viruses it detects. The vast majority affects the Windows platform. Although they are extremely few, there are also virus-like systems Unix / Linux, but no outbreaks similar to that of the Windows virus has been detected in 2010. The rest is mainly aimed at operating systems that are distributed over the past few years, as the 27 viruses - none being dangerous - imposed Mac OS 9 and its predecessors (recorded by John Norstad, author of the antivirus Disinfectant ). Systems are least affected FreeBSD that focuses its development on security, as well as Netware and OS / 2 too few to provide a developer known viruses. Viruses are often subject to false alarms that the rumor spread, bulky freight.Some of them, playing on the ignorance of computer users, they sometimes destroy parts of the operating system completely healthy. The first autonomous software had no purpose they have today. The very first software of this type were mere entertainment, a game between three data of Bell, Core War, created in 1970 in the laboratories of the company. For this game, each player writes a program, then loaded into RAM. The operating system, which has just been multitasking, in turn executes an instruction for each software. The goal of the game is to destroy the opposing programs while ensuring its own proliferation. The players do not obviously opposing the location of the program. The software is capable of copying itself, repair itself, to move themselves into different areas of memory and "attacking" the software by writing random opponent in other memory areas. The game ends after a set time or when a player sees all its programs inactive or destroyed. The winner is the one that has the largest number of active copies. This is exactly the principles of programming viruses.In 1984, the magazine Scientific American presented a computer game design consisting of small programs that come into s'autoreproduisant fight and trying to inflict damage on opponents, thus setting the stage for future viruses. In 1986, the ARPANET was infected by Brain, virus renaming all boot disks system (C) Brain. The creators of this virus gave them their name, address and phone number because it was an advertisement for them.The virus is a classic piece of program, often written in assembler, which fits into a normal program, most often at the end but also at the beginning or the middle. Each time the user runs the program "infected", it activates the virus the opportunity to get integrated into other executable programs. Moreover, when it contains a payload, it may, after a certain time (which can be very long) or a special event, perform a predetermined action. This action can range from a simple message harmless to the deterioration of some functions of the operating system or damage to files or even complete destruction of all data on the computer. One speaks in this case "logic bomb".A boot virus installs a boot sector of a boot device: hard drive (the main boot sector, the "master boot record, or that of a partition), floppy or whatever. It replaces a boot loader (or boot program or "bootloader") entered (by copying the original elsewhere) or created (on a disc or there was none) but does not modify a program like a normal virus, when it replaces an existing startup program, it acts like a virus "prepend" (which is inserted at the beginning), but the fact of infecting a virgin device of any software startup differs from classical virus, which never attacks to "nothing."Macro viruses that attack software macros in Microsoft Office (Word, Excel, etc..) Through VBA Microsoft. For example, adhering to the normal.dot template in Word, a virus can be activated every time the user runs the program. Viruses, worms, appeared around 2003, having experienced a rapid development in the years that followed, are classic viruses because they have a host program. But similar to the worms (in English "worm") because:Their mode of propagation is linked to the network, like worms, usually via the exploitation of security vulnerabilities.Like worms, their action is discreet and non-destructive to users of the infected machine.Like worms, they continue to set broad goals, such as distributed denial of resources attack or DoS (Denial of Service) to a server with thousands of infected machines connecting simultaneously. [ref. necessary] The batch-type virus, which emerged in the days when MS-DOS operating system was in vogue, viruses are "primitive." Although able to reproduce and infect other batch files, they are slow and have very low infectivity. Some programmers have been up to create encrypted and polymorphic viruses Batch. This is a real technical feat Batch as the language is simple and primitive.Other threats exist in IT, it often distinguished by the absence of reproductive system that characterizes the viruses and worms, the term "malicious software (" malware "in English) is more appropriate in this case. The term computer virus was created by analogy with the virus in biology: a computer virus uses its host (the computer it infects) to reproduce and spread to other computers. Like biological viruses, where the genetic diversity slows growth chances of a virus, computer systems and what are the most popular software that are most affected by viruses: Microsoft Windows, Microsoft Office, Microsoft Outlook, Microsoft Internet Explorer, Microsoft Internet Information Server... Professional versions of Windows (NT/2000/XP Pro) to manage rights in a professional manner are not immunized against these stealthy invaders.The commoditization of Internet access was a major factor in the rapid widespread dissemination of the latest viruses. This is mainly due to the ability of viruses to appropriate email addresses found on the infected machine (in the address book but also in the messages or archives visited web pages or messages to newsgroups ). Similarly, the interconnection of computers in local networks has amplified the ability to spread viruses that find this way more potential targets. However, systems with limited distribution are not affected proportionately. The majority of these systems, as variants of the architecture UNIX (BSD, Mac OS X or Linux), using standard management rights of each user allowing them to avoid the simplest attacks, the damage is so normally confined to areas accessible only to users, saving the base operating system. Legal viruses.Author Brayden Alexander from http://www.free-antivirus.coArticle Source: http://EzineArticles.com/expert/Brayden_Alexander/801144Article Source: http://EzineArticles.com/5219148
Fighting Spam - Is It A Loosing Battle?
By Coenraad De Beer In June this year, Neo from WebProWorld started a very interesting discussion on spam. Although his post mainly revolved around forum spam, he did touch a very actual topic. Spam is not only limited to one medium only, spam is a much bigger problem than most people realise. We have to deal with forum spam, search engine spam, e-mail form spam, guest book spam (for those who still use guest books on their websites), article spam (yes article syndication can also turn into annoying spam), IRC spam, blog spam, comment spam, ebook spam, affiliate network spam, mobile phone spam, and of course the infamous unsolicited junk e-mails. I am sure I missed a couple, but I think you get the picture, spam has infiltrated almost every digital form of communication. No wonder people become pessimistic about fighting spam.Some interesting reasoning came to light during this discussion on WebProWorld. One thing that sticks out its head in every discussion about spam is the apathetic approach towards spam. The attitude of "spam has always been a problem and will always be, live with it, accept the problem, you cannot change it, nor can you fix it". There is no merit in any of these statements, so lets take a closer look at them and I will show you why. "Spam has always been a problem". Really? Spam started to become a problem when people discovered its marketing potential. Spam wasn't a problem in the early days of the Web, we allowed it to become a problem by accepting the problem. Yes people got punished back then, but the spam volumes increased so much that it became impossible to punish every single spammer. Companies seem to be more concerned about treating the symptoms (with spam filters) than attacking the root of the problem. The right statement would be: "Spam has always been allowed to be a problem.""Spam will always be a problem". Do we know for certain? Spam may eventually cause the collapse of the e-mail communication system and how do something remain a problem if the infrastructure is gone? If you believe that spam will always be a problem, then you obviously believe that whatever replaces e-mail will also fall victim to spam. Probably, but the creators of a new communication infrastructure will be complete idiots if they allow history to repeat itself. Spam has become a problem because of crippling legislation and in certain cases a total lack of legislation. How can we battle spam if legislation allows spammers to spam you until you tell them to stop? Its like allowing murderers to kill you until you tell them to stop. Can you see how ridiculous our current spam legislation is, spam will always be a problem, as long as we allow useless laws to regulate it."Live with it, accept the problem, you cannot change spam, nor can you fix it". People change, they adapt to their environment. Our kids are growing up with spam, so it will have a far smaller effect on them than it had on us. Those of us who grew up with commercials and ads displayed during our favourite TV shows, have developed a kind of blindness to these ads. Our children will also develop spam blindness over time, they will not respond to spam as easily as we do. It is a matter of education and removing the ignorance. Spam only works because people continue to respond to them.According to an article by Michael Specter, Damn Spam The losing war on junk e-mail, spammers usually need to send a million e-mails to get fifteen positive responses, for the average direct-mail campaign, the response rate is three thousand per million. With a response rate as little as that you can easily see where spam could be heading if we can limit the response rate to zero. There will be no sense in sending spam anymore. People need to realize what is counted as a response and what they can do to limit accidental responses. Yes, simply by opening the e-mail already counts as a response in many cases.Should we accept spam, should we live with it? Well you can easily ask, should we accept serious crimes like murder, rape and armed robbery? Just think what would happen if we had the same attitude towards these wrongdoings, crimes forbidden by civil law. What is civil law, it is actually common sense. We know it is wrong to steal money from someone else, but we are willing to live with a system where it is acceptable for other people to waste our money. That is exactly what spam is.Conventional advertising demands an investment from the advertiser, making it an unattractive medium for cheap unsolicited bulk advertising. However in the case of spam, the consumer ends up paying for the advertising. Some spammers do not even pay a penny for sending these batches of spam, they have bot networks doing the work for them. These bot networks consist of consumer PC's infected with malware. The one consumer (the sender) unknowingly pays to send the spam and the other consumer (the recipient) unknowingly pays to receive the spam. So the consumer coughs up on both sides of the channel.Brad Taylor, Gmail anti-spam engineer, sees the battle against spam as a war. One side eventually gets tired and anti-spam authorities cannot allow themselves to get tired in this struggle against spam. Sometimes the spammers get tired of trying to fool the spam filters and eventually give up, but only for a short space of time. During this rest period they regroup to find a loophole in the filtering system. Once they discover a way around it, they start spamming again. Stock market spam is a classic example of this roller coaster ride. Stock market spam was quiet for some time and suddenly they started popping up like weed via PDF attachments.Spammers will always try to circumvent the system. Does this mean we should give up trying to beat them at their own game? Absolutely no, spammers annoy us with their unsolicited junk, so if we have means to our disposal to annoy them too, why not use it? The war against spam is far from over, the battle against spam is far from lost, I say bring it on.Coenraad is webmaster and founder of Cyber Top Cops, leaders in Internet security, prevention of online fraud and raising awareness about the importance of reporting spam.Article Source: http://EzineArticles.com/expert/Coenraad_De_Beer/14672