Effective Protect Computer Systems from Computer Viruses - Term Paper Example

Computer Viruses Course Name Name Abstract - Computer viruses are computer programs that replicate themselves and infect computer program systems by merely attaching to any file types, and are spread by using infected files in other computers. The main function of computer viruses is to reproduce, interfere, distort, delete and corrupt normal computer operations. There are different categories of computer viruses and they enter computer systems using varied ways and attach to components of a computer's operating and file systems. Despite their nature of replicating and attaching themselves and causing harm, they can be prevented. Keywords – computer, virus, systems I. INTRODUCTION Computer viruses are destructive in nature and as technology advances so has the nature and the complexity of computer viruses (Filiol, 2005). Computer viruses are a security risk in cyber space and they generate a sense of fear in the ability of unauthorized persons entering into restricted virtual areas with ill intentions. In the recent past, cyber space has been hit by numerous computer viruses that have left devastating effects and loss of billions of dollars in damages on computer users. Among notable computer viruses include the 2004 Mydoom worm that within a day, infected close to 250 million computers globally and the 2007 ILOVE YOU virus and the Storm virus, which infected more than fifty million computers (OECD, 2009). In addition, the 1999 Melissa virus which was so destructive it forced Microsoft among other multinationals to switch off their email systems until the virus was contained (OECD, 2009). These are just but a few of the computer viruses which show how harmful they are to both security and productivity. Understanding what computer viruses are, how they are spread and how they work is important in understanding how to effectively protect computer systems from them. II. COMPUTER VIRUSES Computer viruses are computer software with the ability to replicate itself and attach themselves to various types of files and computer components and they are developed with the intention of interfering, corrupting and deleting computer functions and operations (ITLESL. 2005). It is important to note that not all computer programs which are destructive are defined as computer viruses since not all of them are able to replicate. In the same way, not all computer viruses are destructive since the ability for computer programs to replicate does not constitute to destructiveness (Shelly, et al., 2001). As noted by ITLESL. (2005) what certifies a computer program as a computer virus is its ability to reproduce itself, its capacity to be destructive and its ability to acquire control over other computer components. The scientific expression of a computer virus is SRA or simply self-reproducing automation (Stang, 1992). The lifeline of a computer virus is not only to replicate but also to survive and avoid termination. In contemporary world where everything is interconnected, electronic infections have the added advantage of spreading tremendously fast (Miller, 2001). III. HOW COMPUTER VIRUSES OPERATE Computer viruses generate a life of its own where after it is created, it reproduces and attaches itself to files and computer systems with the aim of surviving and transferring to the next ‘host’ which is another computer following the use of an infected file or computer component (Miller, 2001). According to Stang, (1992) computer viruses are machine specific in that viruses created to attack a specific type of machine such as MSDOS computers cannot infect Macintosh computers. Since viruses are meant to interfere with the computer hardware, they must be created in such a way to deal with machine-level instructions. For example, the Motorola 68000 needs a different type of machine instructions compared with instructions required by 80nnn CPUs and therefore, a computer virus which attacks an Atari ST cannot attack a machine from the IBM PC genre and vice versa. As viruses are transmitted from one computer to the other, they are dormant since they require some sort of electrical surge in order to replicate and activate its ability to destroy (Filiol, 2005). When in the computer machine, the computer virus stays dormant until the program to which it is piggybacked onto is run. According to Stang (1992), at that time, what the virus does is determined primarily on the type of virus where a virus can either replicate in other executable files such as.EXE, .OVL, .SYS and COM among others. Attach to files depending on the type of machine, hide in other computer components such as the hard disk or simply cause destruction to computer systems. Figure 1 demonstrates the various ways viruses attack and transfer from one computer to the other Figure 1; the various ways viruses attack and transfer from one computer to the other IV. COMPUTER COMPONENTS ATTACHED, REPRODUCED AND ATTACKED BY VIRUSES As earlier indicated, computer viruses penetrate into computers using varied means and they affect different parts of the computer depending on how the viruses are programmed or what their functions as designed are. Upon entering a computer machine, a virus remains docile until a computer user unsuspectingly runs it (Stang, 1992). This means that a virus is not active until such a time when the program it is attached to is run or alternatively, a particular pre-established condition has been achieved. Upon activation, what a virus does depend entirely on what it is designed to do and the type of computer components it is programmed to destroy and replicate on (ITLESL. 2005). As discussed by Miller, (2001), among components of the operating and file systems attacked by viruses are boot records where the virus attacks the component of the system utilized to run programs and carry out functions of starting up or shutting down such that as soon as a computer is booted, the virus is activated. The other component infected and attached to by viruses are program files such as .exe,.com, .vol among others and data files (Stang, 1992). Viruses can develop companion files which are files that create files which run on the hard disk. In addition computer viruses can attack the computer using batch files and disk directory (Miller, 2001). According to the author, there are visual basic worms which utilize visual basic programming language to manipulate the computer and carryout tasks. V. CATEGORIES AND TYPES OF VIRUSES There are four major categories of computer viruses among the basic virus which is a small software infection which attaches on real computer programs and upon the running of the program; the virus is activated where it replicates itself through attachment to other computer files and programs. There is email viruses which are electronic infections spread through email messages, reproduced by automatically dispatching themselves to thousands different email addresses at a go (Shelly, et al., 2001). Among notable email viruses are those that bring messages informing email account holders they have won money. The other category of viruses is worms which are viruses which utilize computer networks and security gaps to reproduce (OECD, 2009). A worm basically identifies within a network a computer machine with similar security gaps and replicating themselves to the identified machines (ITLESL. 2005). There are Trojans which are viruses that are attached to games applications and as one plays the game, the virus erases the computer’s hard disk (Filiol, 2005). A notable feature of Trojans is that unlike other viruses, Trojans do not reproduce themselves automatically (Miller, 2001). Within these four categories of viruses, there are numerous types of viruses such as polymorphic viruses which change their attributes as they attack a computer, stealth viruses that actively seek to conceal themselves from the system software, sparse infectors. Armored viruses which are designed to make erasing hard to do, space filler viruses that seeks to establish a constant file size as they attack to avoid detection. Another is tunneling viruses, which hide under an antivirus as they attack and virus droppers which are programs which put viruses in the computers but are not by themselves real viruses among others (OECD, 2009). Once computer viruses attacks the computer systems without the user’s knowledge there are varied signs that a user can identify to know when a virus has attacked. Among these signs as discussed by Miller (2001) includes failure of the computer system to start up, missing files, programs taking excessively long to open. The system begins actions such as sending messages to people in the personal directory, pop up messages on the PC monitor such as ‘You have been punkd’ and often the computer may produce beeping and squealing noises from its speakers. VI. WAYS TO SAFEGUARD THE COMPUTER AGAINST COMPUTER VIRUSES Despite the ability of computer viruses to camouflage, replicate, attach themselves on computer components, cause harm, and corrupt the computer. There are measures, which can be taken to ensure viruses are not able to enter into the computer and when they are able to enter, they are effectively dealt with and eradicated and ensure they are unable to replicate and transfer infections to other computers. The most basic prevention measure against computer viruses is to install an internet firewall and an anti-virus program which ensures viruses are not only detected but also screened and destroyed automatically (Filiol, 2005). According to the I.T.L. Education Solutions Limited, an antivirus is a computer software utility that is installed in a computer and scans the computer hard disk to identify and detect viruses and eradicating them accordingly (ITLESL. 2005). An anti virus software identifies changes and activities within the computer that are common in case of a viral infection (OECD, 2009). Carrying out regular computer scan with updated antivirus software ensures viruses that might have remained undetected or those that might have overpowered outdated spywares and antivirus software are detected and erased permanently (Stang, 1992). Figure 2 illustrates how an antivirus operates. Since viruses have the ability to erase everything such as information within a computer systems causing irreversible damage, which costs additional resources in terms of time and money to reproduce, and keeping regular backup of files and programs is crucial. Keeping copies ensures that incase the viruses are able to penetrate the computer security system and crashes the system, one has only to use to copies and outmaneuver the effects of a virus attack (Shelly, et al., 2001). Switching off the email preview functions, scanning any storage devices such as floppy disks, DVDs, CDs, USBs and other devices connected to the PC such as cameras and mobile phones should be done to ensure if they are infected with a virus, the virus is not transferred into the computer (Filiol, 2005). Storage devices are the medium often utilized to transfer virus from one computer to the other. Safeguarding one’s storage devices such as write protecting ensures that once they are inserted in a computer that may have a virus, the write protect feature on the storage devices protects them from a computer viral attack (ITLESL. 2005). It is fundamental to use the installed anti-virus computer program to scan files and documents downloaded from the internet, any attachments received from the internet or through email and ensuring attachments from unknown sources remain unopened (OECD, 2009). Keeping up to date with news about viruses ensures one is on alert when a virus such as Melissa virus is on the loose. Figure 2; how an antivirus operates Ensuring a computer system is effectively and efficiently protected against computer viruses is easier said than done because the computer networks are increasingly becoming open which enhances the level of vulnerability to computer viral attack. In addition, preventing viral attacks is significantly depend on the user’s agility and use of updated antivirus software since new form of viruses are being developed each passing hour and the type and form of viruses created are increasingly complicated and sophisticated to deal with hence, requiring sophisticated security systems to deal and protect against these viruses (Shelly, et al., 2001). Figure 3 illustrates a network that is effectively protected from viral attacks Figure 3; a network that is effectively protected from viral attacks VII. SUMMARY Advancement in technology has seen the rate of internet insecurity rise as people are now able to develop new forms of computer viruses that are not only lethal but also complex and sophisticated to deal with. Computer virus is computer software with the ability to replicate itself and attach itself to various types of files and computer components and it is developed with the intention of interfering, corrupting and deleting computer functions and operations. Understanding how the various types and forms of viruses, how they operate and where they attack are fundamental in designing security systems to prevent viral attack. As highlighted in the report, computer viruses are categorized into Trojans, basic viruses, email viruses and worms. When viruses are transmitted they are dormant and they are activated when the program they are attached to is run. Thereafter, the virus works depending on the function is was programmed for whether it is to replicate, destroy or hide to avoid detection. One can effectively and efficiently safeguard their computer from viruses by installing an internet firewall and using updated antivirus software regularly. It is crucial to scan downloaded files and documents, deleting attachments from unknown sources, keeping updated with news on virus alerts and scanning storage devices such as USBs. References [1]G.B. Shelly, T.J. Cashman, and M.E. Vermatt, “Discovering computers 2002: Concepts for a digital world”, Boston, MA: Course Technology, 2001. [2] ITLESL, “Introduction To Information Technology”, New Delhi: Pearson Education India, 2005 [3] D.J. Stang, “Computer Viruses”, London: DIANE Publishing, 1992. [4] M. Miller, “Special Edition Using the Internet and Web”, Sidney: Que Publishing, 2001. [5] E. Filiol, “Computer Viruses: From Theory to Applications”, Berlin: Birkhäuser, 2005. [6] OECD, “Computer Viruses and Other Malicious Software: A Threat to the Internet Economy”, London: OECD Publishing, 2009 Read More