SYSTEM SECURITY AND ITS MAINAINANCE

SYSTEM SECURITY AND ITS MAINAINANCE

INTRODUCTION:

You need to know your enemies before you can attempt to defeat them. You must know to differentiate between different types of malicious code and tell whether your computer is affected or not.
Life as we know it would be handicapped without computers. From basic communication, finance and even medical science. Computers control just about everything that life in a modern society depends on. In the ideal world man should respect such powers and work towards bettering it to the progression of the civilization. Unfortunately, that ideal world does not exists, which is why great breakthroughs are often followed by the people who are hell-bent on bring it all down. These people see only the weakness of the innovation of technology and will go to any extent to exploit it, simply because they can. Different methods are there to destruct or weaken the innovation of the technology, the different method is to create a virus, different software Trojans like FTP Trojans ,proxy Trojans, Dental Or Service Attack Trojan. There are different ways to avoid the infection that has been by the hacker or the person with not a good intention. This affects the performance of the machine. Different patching software are provided by Windows Operating System which helps to patch the error or remove the error of the software.


BRIEF HISTORY OF VIRUS

Once upon a time…
The when and the where of the very first virus is a little fuzzy to history. The first program which showcased properties of what we now call viruses we called as Elk Cloner, a program for the then popular Apple II: this was in 1981. Elk Cloner was quite the fairy-tale character.
With viruses suddenly and irritingly popping up from the most unlikely of sources, the time was now for saviours. People were desperate for solutions. And so there appeared antidotes. Like the Malady, the first cure is hard to pinpoint. Which was the first antivirus, is difficult were introduced. And when it rained, it poured. Antivirus solution were plenty including software from IBM, Mcafee, Digital Dispatch and Iris.
In 1995,Microsoft released the revolutionary Windows 95 and antivirus companies were worried that nobody would need them anymore. The most common viruses were still boot viruses that work on DOS, but wouldn’treplicate on
Windows 95. Little did they know… sometime the same year. Macro viruses appeared. These Viruses worked in the
MS-Word environment. The Antivirus industry would keep its job.
Come 1990 and viruses started displaying a variety of characteristics. These include polymorphism-encrypted viruses where the decryption routine code was variable. Armouring-to prevent antivirus researchers from dissembling a virus and multipartiteable to infect both programs and boot sectors. The first virus was called as “Chameleon”.By april 1991 everyone was talking shots of “Tequila” –a virus which was stealth. Polymorphism and Multipartite;a very real and problematicthreat. Suddenly, viruses became a lot more threating.

WHAT IS VIRUS?
A computer virus may be defined as an executable program that is capable of infecting other computer program by modifying them to include a copy of itself. Just the way people can spread them common cold by being in contact with the other people a computer virus come in contact with the other program to ‘infect’ them. Viruses can severely damage to your computer which will cost you dear. The damage could consist of important files destroyed, corrupted data ,slowing down the infected computer,interrupted or unexpected closing of important programs,or it could be any or all of these.

HOW VIRUS WORKS

There are tens of thousands of viruses out there,and new ones are every day.It is difficult to come up with a generic explaination of how viruses work, since they have variations in the way they infect or the way they spread.We’ve taken some broad categories that are commonly used to describe various types of viruses.

FILE VIRUSES (Parasitic Viruses)

File viruses are pieces of code that attach to executable files,drivers files,and are activated when the host program is run.
After activation,the virus may spread itself by attaching itself to other programs in the systems,and also carry out the malevolent activity it was programmed for.Most file viruses spread by loading themselves in systems memory and looking for any other programs located on the drive.If it finds one,it modifies the program’s code so that it contains and activates the virus the next timeit’s run.It keeps doing this over and over until it spreads across the system,and possibly to other systems that the infected program may be shared with.
Besides spreading themselves,these viruses also carry some type of constituent that can be activated immediately or by a particular ‘trigger’.The trigger could be a specific date,or the number of times the virus has been replicated.

BOOT SECTOR VIRUSES
A boot sector virus affects the boot sector of a hard disk,which is a very crucial part.The boot sector is where all information about the drive is stored,along with a program that makes it possible for the O.S. to boot up.By inserting it’s code into the boot sector,a virus guarantees that it loads into memory during every boot sequence.

MACRO VIRUS

Macro viruses infect files that are created using certain applications or programs that contains macros.These include Microsotf office documents such as Word documents,Excel spreadsheets,Powerpoints presentations,Access database and other similarapplications files such as Corel Draw etc.
Macro viruses are platform-independent they can spread between windows.The first Macro virus was written for Microsoft Word and was discovered back in August 1995. Today, there are thousands of macro viruses in existence-some example are Relax, Melissa.A and Bablus.

NETWORK VIRUS
Once it infects a new system,it searches for poetential targets by searching the network for other valnerable systems.Once a new vulnerable system is found, the network virus infects the other system, and thus spreads over the network. Some of the
most notorious network viruses are Nimda and SQLQlammer.

E-MAIL VIRUS
It is a form of macro virusthat spread itself to all contacts located in host’s e-mail address book.If any of e-mail recipient open the attachment of the infected mail, It spreads to the new host’s address book and then proceeds to sends itself to all those contacts as well. These days, e-mail viruses can infect host’s even if the infected e-mail is previewed in a mail client.One of the most common and destructive e-mail virus is the ILOVEYOU virus.

AVOIDING INFECTION

There are ways to avoid infection by following a set of simple guidelines:
Ø Make sure you have a clean boot CD handy all the time.
Ø If your anti-virus has an option of making a bootable CD, take some time off to make one of those.
Ø Use a well-reputed anti-virus software and update it daily.
Ø Make sure your anti-virus automatically scan any newly inserted disk for virus,especially if you tend to exchange between your office and home computers.
Ø Avoid opening mails with attachment unless you are absolutely sure they are from the trusted sources.
Ø If you are using a e-mail client on your computer then disable the message preview pane.This way you can filter the message.
Ø Keep all your documents and important programs backed up on a CD or any other storage media.

COMMON SYMPTOMS AND PRECAUTIONS

The symptoms which you should look out for are as follows:

Ø Your computer always stops responding when you try to use certain software.This could also take place due to corruption of an essential file required by the software.
Ø You received an e-mail message that has a strange attachment. When you open the attachment, dialog boxes appear, or a sudden degradation in systems performance occurs.
Ø There is a double extension on an attachment that you recently opened, such as .jpeg .vbs or .gif .exe.
Ø An anti-virus program is disabled for no reason and it cannot be restarted.The computer may not allow reinstallation of anti-virus.
Ø New icons that you did not place on the desktop appear ,and are not associated with any recently installed programs.
Ø Strange sounds or music plays from your speakers unexpectedely.
Ø A program disappears from the computer . and you did not uninstall it.
Ø Windows will not start because certain critical system files are missing, and you receive error messages listing those files.
Ø The computer runs very slowly and it takes long time to start.

DIFFERENT TYPES OF TROJANS ARE:

FIREWALL AND OTHER METHOD OF PROTECTION

Firewalls were only used as a security method by the network administrator to safeguard their server by unauthorized access by the hacker. The new age of the internet threats and the rise in the malicious software means that firewall are somewhat of the necessity for every computer.
A firewall is a software application or hardware device that functions in a networked environment to prevent certain communication that’s forbidden by security policy. It filters all network packets, and determine whether to allow or block them.
When an unauthorized entry is attempted the firewall blocks it and also make your computer invisible to external network and you can’t attack what you see.

PATCHING FOR SECURITY

The stark reality of life – all software must be patched at some time or another. No matter how perfect a software seems when it is released , people are bound to find bugs and security hole in the code. So to fix these niggling problems, software companies release patches on a regular basis.

So which software you need to update ? Ideally, you should update all drivers and programs that yopu use on a regular basis.Your top priority,however should be to keep the operating system updated with the latest patches. Luckily,newer version of OSes Windows 2000 and Windows Xp already come with a windows patch utility that informs youof any new security fixesreleased for the OS.

If you make updation ritual,your computer will be better to handle the majority of exploits that come out. Mnay distribution companies offer this service.

A lot of exploits happens in every day programs such as browser and instant messanger, which can leave you computer to Trojan’s or hacker attack.

TO PREVENT US FROM VIRUS DIFFERENT TYPE OF ANTIVIRUS SOFTWARE ARE

1.McAfee VirusScan Home 9.0
McAfee Antivirus package have always been a great option, but if there was one particular flaw that made some user shy away from it, was complicated interface. But this version provide a better and easy user interface.2.Spyware Eliminator 4.0
When it comes to spyware constantly eating up your resource and the bandwidth, ther is no such thing to be safe.Spyware Eliminator does what its name suggests eliminating spyware. It gives you real time tracking and the blocking capabilities that’s why you prevent rather than cure. It also offers ‘consumerwave’ a new section that separates legitimate award companies from the actual spyware so you know what to delete, uninstall or keep.



THE SECURITY PROVIDED BY EACH SOFTWARE AND DEVICE ARE:

REFERENCES

Computer Viruses For Dummies By Peter H.George
Virus Proof By Phil Schmauder

CONCLUSION:

You need to know your enemies before you can attempt to defeat them. You must know to differentiate between different types of malicious code and tell whether your computer is affected or not.
Life as we know it would be handicapped without computers. From basic communication, finance and even medical science. Computers control just about everything that life in a modern society depends on. In the ideal world man should respect such powers and work towards bettering it to the progression of the civilization. Unfortunately, that ideal world does not exists, which is why great breakthroughs are often followed by the people who are hell-bent on bring it all down. These people see only the weakness of the innovation of technology and will go to any extent to exploit it, simply because they can. But technology is not that weak as they think because different new security like hardware Device and software application is launched and is quite cheap.