Abstract:This paper proposes a scheme to defend distributed denial of service attacks (DDos) based on the source and destination IP address database. The scheme establishes the source and destination IP address database (SDIAD) by observing the normal traffic and storages SDIAD in a three dimension Bloom Filter table. Then this paper cumulates and analyses the new pair of source and destination IP address based on the slide non-parametric cumulative sum (CUSUM) algorithm to detect the DDos attacks quickly and accurately. The secheme updates SDIAD by using a delayed update policy to keep SDIAD timely,accurate and robust. This secheme is mainly applied in the edge router and it can detect the DDos attacks efficiently either the edge router or the last-mile router is the first-mile router. The simulation results display that the secheme do a good performance in detecting DDos attacks.