Date Added: Nov 2011
Distributed Denial Of Service (DDOS) attacks is a critical threat to the internet. Due to the memory less features of the internet routing mechanism makes difficult to trackback the source of the attacks. In this paper, the authors find out the source of the attack with the help of entropy variation in dynamic by calculating the packet size, which shows the variation between normal and DDOS attack traffic, which is fundamentally different from commonly used packet marking techniques. In comparison to the existing DDOS trackback methods, the proposed one posses dynamic entropy variations as per the clients behavior.