A denial-of-service (DoS) attack is one of the most dangerous attacks available to hackers and cyber-criminals because it is relatively easy to execute and it often results in total destruction of the victim’s network or systems.
In the majority of cases, a hacker will carry out a DoS attack to deny a victim service that they do not want to provide.
How do you know if you are targeted in DDoS Attack?
A denial-of-service attack is an attack against an online or networked system, for example, an Internet-connected server, which denies the system any service for a period of time. The victim of a DoS attack will become aware of the issue either through a sudden interruption in service or by a message stating that the system is being blocked. In extreme cases, the message will show that a device connected to the network has been brought offline.
Because a DoS attacker does not need to access an organisation’s server to attack it, Web sites are particularly vulnerable to DoS attacks. The Web sites for Microsoft, eBay, Amazon.com, and many other companies have been victims of DoS attacks that resulted in service interruptions to their customers.
As you know, a Web browser loads a Web page by sending a message to a Web server that requests the page. The Web server responds with a message that contains the HTML content of the WebHTMLe, along with an image or other files required to display the Web page in the browser. When a Web browser is used in a DoS attack, it sends thousands of page requests per minute to the Web server with the goal of overloading the server.
In some cases, each of the page request messages has a false return address, so the Web server consumes processing resources in an attempt to solve the problem. As more page requests arrive at the Web browser, and as the efforts to solve the problem and to process the new requests accumulate, the server becomes overloaded and unavailable to process legitimate requests. Ultimately, the server shuts down.
In a distributed denial-of-service (DDoS) attack, the attacker takes control of one or more computers without the owner’s permission and uses those computers to launch a DoS attack on other computers, servers, or networks. Most DDoS attacks are initiated after the attacking computers are infected with Trojan horse programs. Each Trojan horse program is coded to open and launch a DoS attack on the same date and time.
Is there anything you can do to protect yourself from an attack?
As with any form of attack, the best defence against DoS attacks is to be properly protected from such attacks in the first place. To protect against these types of attacks, servers require some form of protection, the basic level of protection for which is to monitor them with a monitoring tool to look for any unusual traffic.
Although this is the basic level of protection required by servers, it is often the case that such tools will report issues even if the attack is a DoS attack. However, once the attack has started it is often too late to block it and if the server was to go offline, services on the server may be affected.