Recently, we have a problem about an attack generated by a botnet which consists of a group of compromised computers called bots. An attacker called botmaster controls it and a botnet invokes an attack such as scanning and DDoS attack. In this paper, we use the 3D-visualization to investigate the change of attack according to the darknet traffic. As a result, we discover the attack in which several source IP addresses transmit packets to a single destination within a short period of time. In addition, we find that the packet size and the destination port number are identical on its attack. Furthermore, we propose the method to detect this attack called behavior of collaborative attack. In our proposal, we focus on the number of source IP addresses which transmit packets to the single destination. We detected this packet and the rate of packet with the same packet size and destination port number occupied about 90% of the set unit of extracted packet.