Distributed Denial of Service (DDoS) Attacks

What is a Denial Of Service Attack?

A denial of service attack (DOS) is an attack through which a person can render a system unusable or significantly slow down the system for legitimate users by overloading the resources, so that no one can access it.
If an attacker is unable to gain access to a machine, the attacker most probably will just crash the machine to accomplish a denial of service attack,this one of the most used method for website hacking

Types of denial of service attacks

There are several general categories of DoS attacks.Popularly, the attacks are divided into three classes:

bandwidth attacks,
protocol attacks
logic attacks



What is Distributed Denial of Service Attack?

In DDOS attack, The attacker launches the attack using several machines. In this case, an attacker breaks into several machines, or coordinates with several zombies to launch an attack against a target or network at the same time.
This makes it difficult to detect because attacks originate from several IP addresses.If a single IP address is attacking a company, it can block that address at its firewall. If it is 30000 this is extremely difficult.

Damages made By Denial of service attack:

Over past years Denial of service attack has made huge amount of damage,Many of the have been victimed of this attack
Its Real,On February 6th, 2000, Yahoo portal was shut down for 3 hours. Then retailer Buy.com Inc. (BUYX) was hit the next day, hours after going public. By that evening, eBay (EBAY), Amazon.com (AMZN), and CNN (TWX) had gone dark. And in the morning, the mayhem continued with online broker E*Trade (EGRP) and others having traffic to their sites virtually choked off.

This attack also recently hit twitter on 6th August 2009,lot of people had trouble on logging on twitter,It was brought down by denial of service attack,They tired up there server so no one can get on log on it.Websites like facebook,ebay etc have also been victim of this attack.
Now i will show you how you can flood a website with Denial of service attack. For this tutorial we will be using one of the most effective and one of the least known tools called "Low Orbit Ion Cannon", created by Anonymous members from 4chan.org, this program is one of the best for DDoS'ing, and I have successfully used it to DDoS websites. An internet connection as bad as mine (2,500 kb/s) was able to keep a site down for a day with this program running. Remember that this tool will work best with high internet speeds, and try not to go for impossible targets (like Google, Myspace,Yahoo). LOIC is used on a single computer, but with friends it's enough to give sites a great deal of downtime.

Prerequisites: Download LOIC (Low Orbit Ion Cannon). Open up LOIC.
(I am not giving a download link because then i will be accused for exiting hackers,try goggling).

Step 1: Type the target URL in the URL box.

Step 2: Click lock on.

Step 3: Change the threads to 9001 for maximum efficiency.

Step 4: Click the big button "IMMA FIRIN MAH LAZAR!"

Feel free to tweak around with these settings and play around with the program to get the best performance. Then minimize and go do whatever you need to do, the program will take care of the rest!