摘要:Flood attacks means a network becomes so weighed down with packets, caused by the attackers. It prevents packets being sent/received between the nodes in the network. There are many methods adopted to prevent flood attacks in other networks, but none has been installed successfully for DTN’s. Disruption tolerant network is a network, developed in such a manner that intermittent communication problems have very low effect on the outcome of the result. However, due to the limited network resources in this network such as buffer space and bandwidth, it is liable to flood attacks. In order to protect resources and defend against flood attacks, the rate limiting technique should be adopted. In which each node must be set up with a restriction over the number of packets it can send to the network and number of duplicates that can be created for each packets, such as rate limit L and rate limit R respectively. However flood attacks are caused even in application level resulting in losses of resources such as CPU and sockets. So, technique for detection of application level floods attacks is implemented by verifying DNS query with a specific tool and validating it with mysql database.