DoS and DDoS in context with computer security

DoS attack refers to denial-of-service attack, while DDoS refers to distributed denial-of-service attack (DDoS attack). DoS is an attempt to make a machine or network resource unavailable to its intended users. Targets of a DoS attack generally consist of the efforts of one or more people to temporarily or indefinitely interrupt or suspend services of a host connected to the Internet. The DoS attacker generally target sites or services hosted on high-profile web servers such as banks, credit card payment gateways, and even root nameservers. The term is generally used relating to computer networks, but is not limited to this field; for example, it is also used in reference to CPU resource management. A distributed denial of service attack (DDoS) occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. These systems are compromised by attackers using a variety of methods.

Why DoS and DDoS are in news?

In May 2012, the hacktivist group “Anonymous” which had weighed in favour of Anna Hazare’s campaign, was in news because it again launched distributed denial of service (DDoS) attacks against Indian websites, including those of the Supreme Court and the All India Congress Committee. This attack was in support of the legislative motion of P. Rajeev of the CPM, seeking annulment of the poorly considered Information Technology (Intermediaries Guidelines) Rules, 2011, which can force hosts to censor user content on the basis of complaints alone. Besides, it was a reaction to an order apparently secured to block file-sharing websites like The Pirate Bay, to protect Dhanush’s movie, 3.