Volume : 2, Issue : 7, July - 2013

Cyber Crime : How Distributed Denial of Service Works

Santosh Mishra

Abstract :

A denial of service is characterized by an explicit attempt by an attacker to prevent legitimate users from using resources. An attacker may attempt to: “flood” a network and thus reduce a legitimate user’s bandwidth, prevent access to a service, or disrupt service to a specific system or a user. We describe methods and techniques used in denial of service attacks, and we list possible defences. In Recently many prominent web sites face so called Distributed Denial of Service Attacks (DDoS). While former security threats could be faced by a tight security policy and active measures like using firewalls, vendor patches etc. these DDoS are new in such way that there is no completely satisfying protection. We find that under persistent denial of service attacks, class based queuing algorithms can guarantee bandwidth for certain classes of input flows.