DOS attack on Twitter and Facebook

Twitter and Facebook were attacked by DDOS (DISTRIBUTED DENIAL OF SERVICE) which led to the site-wide outage for several hours on Thursday suffered periodic slowness and time-outs throughout the day. Also heard few of Google services were also being attacked. Speaking about this attack Max Kelly, chief security officer at Facebookalleged one blogger, who uses the account name "Cyxymu," (the name of a town in the Republic of Georgia)

Kelly also mentioned that “Cyxymu's LiveJournal page wasn't accessible, but a cached version showed that it was updated on Thursday with a message about the denial of service (DOS) attacks on his accounts on the US-based sites. “Now it's obvious it's a special attack against me and Georgians," the message in Russian said.” And he also mentioned that this was the first coordinated attack on the sites, and all the companies involved were working closely on the investigation

However Facebook and Google were able to minimize any impact to their sites, including Blogger, YouTube and Google Sites. Facebook even managed to keep the Cyxymu account accessible to Web surfers from that region


What is this DOS or DDOS are really?
A denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is an attempt to make a computer resource unavailable to its intended users.

How this will be done?
One common method of attack involves saturating the target (victim) machine with external communications requests, such that it cannot respond to legitimate traffic, or responds so slowly. In general terms, DoS attacks are implemented by either forcing the targeted computer(s) to reset, or consuming its resources so that it can no longer provide its intended service or obstructing the communication media between the intended users.

Attacks can be directed at any network device, including attacks on routing devices and web, electronic mail, or Domain Name System servers.

For example, sending an extraordinary amount of electronic mail to someone could fill the computer disk where mail resides. This means that people who use the computer with the full disk cannot receive any new email until the situation changes.

A DoS attack can be perpetrated in a number of ways. The five basic types of attack are:
1. Consumption of computational resources, such as bandwidth, disk space, or processor time
2. Disruption of configuration information, such as routing information.
3. Disruption of state information, such as unsolicited resetting of TCP sessions.
4. Disruption of physical network components.
5. Obstructing the communication media between the intended users and the victim so that they can no longer communicate adequately.

Details regarding DDOS courtesy: Wikipedia and other sources

To know more about this DDOS attacks, types of DDOS attacks and how these will be done in detailed please visit below links
Wiki and cert