Probabilistic packet marking with non-preemptive compensation

A new scheme in probabilistic packet marking (PPM) for IP traceback against denial-of-service attack is presented. Non-preemptive PPM is performed while a marked packet is coming, but compensates the reduction of marking probability in marked-free packets. The nonpreemptive compensation makes the probability of each marked packet arrived at the victim is equal to its original marking probability. This scheme efficiently improves the convergent amount of marked packets required for reconstructing the complete attack path.