HE critical problem of network security in present years is DoS (Denial of Service) attacks. Many techniques are offered by the dynamic field of research, some of these techniques are the packet filtering techniques, pushback message and ICMP [8],[5] trace back. Savage [2] has designed an algorithm called Probabilistic Packet Marking Algorithm which is also called as PPM algorithm. This algorithm is designed for contributing the IP trace back idea. The IP trace back method permits the routers to encode particular data on the attack packets. The routers encode the data based on some programming probability. The victims can build a set of paths which are navigated or traversed by the attack packets when they receive marked packets in sufficient number. As a result of this, the location of attacker can be recognized by the help of victim. Obtaining a built graph is the most significant objective of PPM algorithm [7], a constructed graph which is obtained by the PPM algorithm is similar to the attack graph. The set of paths traversed by the attacker are represented by the attack graph and the constructed graph represents the graph that is obtained from the algorithm of PPM. Savage et al.,[2] have been suggested a technique to fulfill this aim. In this technique the data of the attack graph edges are encoded into the packets of DoS attacks with the help of routers that are present in the attack graph from the victim‘s location. The algorithm of PPM is implemented very specially using two different procedures: