16 February 2012: Locating the source of a Internet attacks
So-called DDOS attacks (distributed denial of service attacks) are an infamous way of shutting down Internet servers. The attack is relatively complex and consists of several stages.
First, the attacker infects a large number of computers around the world with a virus which allows the attacker to override the control of these computers. Second, the attacker directs all these computers to attempt accessing a certain web server simultaneously and repeatedly. Because of this, the victim server becomes overloaded with requests (which arrive hundreds of times more frequently than its normal capacity). During the attack, the victim server cannot serve genuine requests, and might even switch off altogether. The DDOS attack is known, in particular, as a kind of Internet attack which is most often used by authoritarian regimes against independent news web sites.
Resisting DDOS attacks is difficult and needs new approaches applied globally and efficiently throughout the whole Internet. Dr Alexei Vernitski, from the Department of Mathematical Sciences, is involved in a project that is investigating how a small change in how signals are forwarded around the Internet can lead to a possibility to locate the source of a DDOS attack in a precise and efficient way.