Distributed Denial of Service attacks (DDoS) is vulnerable to the internet. It is extremely hard to trace back the source of these attacks. Because of the vulnerability of the original design of the Internet, it's hard to find the actual hackers at present. In this paper, the authors propose a novel mechanism for IP trace-back using information theoretical parameters, and there is no packet marking in proposed strategy. Packet pollutions are overcome and it is also independent of attack traffic patterns.