This article presents information about real-time visualization of network attacks on high-Speed links. Intuitive visualization of ongoing attacks is something that network administrators can make good use of, providing quick perceptual clues before other more complicated analyses kick in. It is demonstrated in this article that such attack visualization can be surprisingly straightforward yet highly informative. Although there are numerous types of malicious attacks against or via the network, denial of-service (DoS) attacks and worm epidemics undoubtedly have been the most notorious recently. The most popular have been the most notorious recently. The most popular type of DoS or distributed DoS (DDoS) attack is flooding, which simply bombards a victim with packets beyond the victim's bandwidth or processing capacity. For instance, the DoS attack on root DNS servers on October 21, 2002 mobilized100 to 200 kilo-packets per second against each victim, blasting 50 to 100 Mb/s of traffic on it.