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Thursday, March 5, 2009

What is difference between a virus, Trojan Horse and Worm




  What is the Difference Between a Virus, Trojan Horse and Worm?

The most common blunder when the topic of a computer virus arises is that people will often refer to a Worm or Trojan Horse as a Virus. While the words Trojan, worm, and virus are used interchangeably, they are not the same. Viruses, worms, and Trojan Horses are all malicious programs that can cause damage to your computer, but there are differences between the three, and knowing those differences can help you to better protect your computer from their often damaging effects.


A computer Virus attaches itself to a program or file so it can spread from one computer to another, leaving infections as it travels. Some viruses cause only mildly annoying effects while others can damage your hardware, software, or files. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it cannot infect your computer unless you run or open the malicious program. It is important to note that a virus cannot be spread without a human action, (such as running an infected program) to keep it going. People continue the spread of a computer virus, mostly unknowingly, by sharing infecting files or sending e-mails with viruses as attachments in the e-mail.


A Worm is similar to a virus by its design, and is considered to be a sub-class of a virus. Worms spread from computer to computer, but unlike a virus, it has the ability to travel without any help from a person. A worm takes advantage of file or information transport features on your system, which allows it to travel unaided. The biggest danger with a worm is its ability to replicate itself on your system, so rather than your computer sending out a single worm, it could send out hundreds or thousands of copies of itself, creating a huge devastating effect. One example would be for a worm to send a copy of itself to everyone listed in your e-mail address book. Then, the worm replicates and sends itself out to everyone listed in each of the receiver's address book, and the manifest continues on down the line. Due to the copying nature of a worm and its ability to travel across networks the end result in most cases is that the worm consumes too much system memory (or network bandwidth), causing Web servers, network servers, and individual computers to stop responding. In more recent worm attacks such as the much talked about Blaster Worm, the worm has been designed to tunnel into your system and allow malicious users to control your computer remotely.



A Trojan Horse is full of as much trickery as the mythological Trojan Horse it was named after. The Trojan Horse, at first glance will appear to be useful software but will actually do damage once installed or run on your computer. Those on the receiving end of a Trojan Horse are usually tricked into opening them because they appear to be receiving legitimate software or files from a legitimate source. The Trojan horse itself would typically be a Windows executable program file, and thus must have an executable filename extension such as .exe, .com, .scr, .bat, or .pif. Since Windows is sometimes configured by default to hide filename extensions from a user, the Trojan horse is an extension that might be "masked" by giving it a name such as 'Readme.txt. exe'. With file extensions hidden, the user would only see 'Readme.txt' and could mistake it for a harmless text file. When the recipient double-clicks on the attachment, the Trojan horse might superficially do what the user expects it to do (open a text file, for example), so as to keep the victim unaware of its real, concealed, objectives. Meanwhile, it might discreetly modify or delete files, change the configuration of the computer, or even use the computer as a base from which to attack local or other networks - possibly joining many other similarly infected computers as part of a distributed denial-of-service attack. When a Trojan is activated on your computer, the results can vary. Some Trojans are designed to be more annoying than malicious (like changing your desktop, adding silly active desktop icons) or they can cause serious damage by deleting files and destroying information on your system. Trojans are also known to create a backdoor on your computer that gives malicious users access to your system, possibly allowing confidential or personal information to be compromised. Unlike viruses and worms, Trojans do not reproduce by infecting other files nor do they self-replicate.  


Added into the mix, what is called a blended threat? A blended threat is a sophisticated attack that bundles some of the worst aspects of viruses, worms, Trojan horses and malicious code into one threat. Blended threats use server and Internet vulnerabilities to initiate, transmit and spread an attack. This combination of method and techniques means blended threats can spread quickly and cause widespread damage. Characteristics of blended threats include: causes harm, propagates by multiple methods, attacks from multiple points and exploits vulnerabilities.



To be considered a blended thread, the attack would normally serve to transport multiple attacks in one payload. For examplem it wouldn't just launch a DoS attack  it would also install a backdoor and damage a local system in one shot. Additionally, blended threats are designed to use multiple modes of transport. For example, a worm may travel through e-mail, but a single blended threat could use multiple routes such as e-mail, IRC and file-sharing sharing networks. The actual attack itself is also not limited to a specific act. For example, rather than a specific attack on predetermined .exe files, a blended thread could modify exe files, HTML files and registry keys at the same time  basically it can cause damage within several areas of your network at one time.  



Blended threats are considered to be the worst risk to security since the inception of viruses, as most blended threats require no human intervention to propagate.

  Combating Viruses, Worms and Trojan Horses :  



The first steps to protect your computer are to ensure your operating system (OS) is up-to-date. This is essential if you are running a Microsoft Windows OS. Secondly, you should have anti-virus software installed on your system and download updates frequently to ensure your software has the latest fixes for new viruses, worms, and Trojan Horses. Additionally you want to make sure your anti-virus program has the ability to scan e-mail and files as they are downloaded from the Internet. This will help prevent malicious programs from even reaching your computer. If this isn't enough protection, then you may want to consider installing a firewall as well.

A firewall is a system which prevents unauthorized use and access to your computer. A firewall can be either hardware or software. Hardware firewalls provide a strong degree of protection from most forms of attack coming from the outside world and can be purchased as a stand-alone product or in broadband routers. Unfortunately, when battling viruses, worms and Trojans, a hardware firewall may be less effective than a software firewall, as it could possibly ignore embedded worms in out going e-mails and see this as regular network traffic. For individual home users, the most popular firewall choice is a software firewall. A good software firewall will protect your computer from outside attempts to control or gain access your computer, and usually provides additional protection against the most common Trojan programs or e-mail worms. The downside to software firewalls is that they will only protect the computer they are installed on, not a network.  

It is important to remember that on its own a firewall is unable to get rid of your computer virus problems, but when used in conjunction with regular operating system updates and a good anti-virus scanning software, it will add some extra security and protection for your computer or network.







Tuesday, February 24, 2009

Warren Buffet's advice for 2009

  • We begin this New Year with dampened enthusiasm and dented optimism. Our
    happiness is diluted and our peace is threatened by the financial illness
    that has infected our families, organizations and nations. Everyone is
    desperate to find a remedy that will cure their financial illness and help
    them recover their financial health. They expect the financial experts to
    provide them with remedies, forgetting the fact that it is these experts who
    created this financial mess.

    Every new year, I adopt a couple of old maxims as my beacons to guide my
    future. This self-prescribed therapy has ensured that with each passing
    year, I grow wiser and not older. This year, I invite you to tap into the
    financial wisdom of our elders along with me, and become financially wiser.

      Hard work: *All hard work bring a profit, but mere talk leads only to   poverty.

      Laziness:* A sleeping lobster is carried away by the water current.

      Earnings:* Never depend on a single source of income.. [At least make   your Investments get you second earning]

      Spending:* If you buy things you don't need, you'll soon sell things   you need.

      Savings:* Don't save what is left after spending; Spend what is left   after saving.

      Borrowings:* The borrower becomes the lender's slave..**

      Accounting:* It's no use carrying an umbrella, if your shoes are  leaking.

      Auditing:* Beware of little expenses; A small leak can sink a large   ship.

      Risk-taking:* Never test the depth of the river with both feet. [Have an alternate plan ready]

      Investment:* Don't put all your eggs in one basket.


     I'm certain that those who have already been practicing these principles
    remain financially healthy. I'm equally confident that those who resolve to
    start practicing these principles will quickly regain their financial
    health.

    With Best Regards,
    Warren Buffet

     

Thursday, February 28, 2008

The World as We Know It: 8 Ways to Feel Good When You Low

The World as We Know It: 8 Ways to Feel Good When You Low

Monday, February 25, 2008

Prediction for 2008 - Warren Buffet - 3rd Richest Man in the world


.
Web Bug from http://geo.yahoo.com/serv?s=97490481/grpId=6548896/grpspId=1720193918/msgId=21861/stime=1203791780/nc1=4096937/nc2=4026936/nc3=3 "Eight for '08"
Warren Buffett became one of the wealthiest people in the world by
making predictions and putting money behind those predictions. Every
time he buys a stock or a business or some other investment, he's
forecasting the future.

Judging by the incredible returns of his holding company Berkshire
Hathaway, Buffett and his colleagues are very good at making those
predictions.

Of course, it helps when you can give your predictions plenty of time
to come true. That's one reason Buffett's favorite holding period for
investments in "outstanding businesses with outstanding managements"
is "forever." After all, "We don't get paid for activity, just for
being right. As to how long we'll wait, we'll wait indefinitely."

1. Recessions can't be avoided forever.

In the last few days, Buffett told that if unemployment picks up
significantly, the "dominoes" will fall and the U.S. economy will fall
into recession in 2008. He's not sure, however, that unemployment
will go up next year. In fact, he's surprised that all the weakness
we're seeing in housing hasn't affected the jobs market ... yet.
Here's what he is sure about: "It is the nature of capitalism to
periodically have recessions. People overshoot."

2. We'll survive future recessions just as we've survived past
problems.

As Buffett told in August, "We've got a wonderful economy... There's
never been anything like that in the history of the world. We live
seven times better than the people did a century ago on average...
We've had problems all along. If you look at the last century, we had
that Great Depression and World War Two, we had the Cold War, we had
the atomic bomb, but the country does well."

3. Recessions will create opportunities.

"I made by far the best buys I've ever made in my lifetime in 1974.
And that was a time of great pessimism and the oil shock and
stagflation and all those sort of things. But stocks were cheap."

4. All stocks won't be cheap.

Like Ted Williams waiting for the right pitch, a successful investor
waits for the right stock at the right price, and it doesn't happen
every day. "What's nice about investing is you don't have to swing at
pitches. You can watch pitches come in one inch above or one inch
below your navel, and you don't have to swing. No umpire is going to
call you out." You get in trouble, Buffett says, when you listen to
the crowd chanting "Swing, batter, swing!"

5. The crowd will make mistakes.

Buffett cites this piece of advice from his mentor Benjamin Graham:
"You're neither right nor wrong because other people agree with you.
You're right because your facts are right and your reasoning is right—
and that's the only thing that makes you right. And if your facts and
reasoning are right, you don't have to worry about anybody else."

6. Investors will mistakenly think falling stock prices are bad.

"If they reduce the price of hamburgers at McDonald's today I feel
terrific. Now I don't go back and think, gee, I paid a little more
yesterday. I think I'm going to be buying them cheaper today. Anything
you're going to be buying in the future, you want to have get cheaper.

7. Good times will prompt bad decisions.

In his 2000 Letter to Berkshire shareholders, Buffett compared the
crowd that buys big when prices are high to Cinderella at the ball.
"They know that overstaying the festivities - that is, continuing to
speculate in companies that have gigantic valuations relative to the
cash they are likely to generate in the future - will eventually bring
on pumpkins and mice. But they nevertheless hate to miss a single
minute of what is one helluva party. Therefore, the giddy participants
all plan to leave just seconds before midnight. There's a problem,
though: They are dancing in a room in which the clocks have no hands."

8. There will be more dancing at another wild party followed by
another painful hangover.

Looking back at the Internet bubble, Buffett is quoted as saying,
"The world went mad. What we learn from history is that people don't
learn from history."

__,_._,___

--

Wednesday, January 23, 2008

Mostly Harmless: java Exception - Unknown Source

Many time java engineer is in dilema of exception called Unknown Source and it take
hours and some whole day to track the source of exception by tracking entire code flow

Here is very good tips to tackle from such kind of error, it is basically because of
ant level configuration in build.xml

Please visit Nilesh Bansal blog for more details insight on it

Mostly Harmless: java Exception - Unknown Source

Happy Debugging

Sunday, January 13, 2008

Golden Rules to earn money in Stock Market



1. Keep patience - that's most important rule in stock market.
2. Always follow the market trend.
3. Do fundamental analysis of any stocks before investing in to Stock
Market.
4. Invest equal amount of money in 3-4 scripts & keep your eyes on your
stock holding and market trend to get good returns.
5. Strictly follow stop loss for any stocks.
6. Don't loose your focus.
7. Book Profit on every rise,so always you will get benefited.
8. Keep your profit aside and rotate the principal amount again in stock
market.
9. Don't forget any of above rule & follow *Tips4Trade tips*, you will be
always in profit.

Thursday, December 20, 2007

Warren Buffett Talk / VIdeo on Stock picking and Investing - Part 1