Distributed Denial of Service (DDoS) attack includes by sending large volume of enormous requests to the server or site and it will unable to handle the enormous requests, and the server remains offline for some time depending upon the attack. Flooding attack is one type of the DDoS attack. For the detection of DDoS flooding attack, one of the approaches is used as multi-dimensional sketch design by integrating with Hellinger Distance (HD) analysis. The HD analysis can be used to monitor the network flows. Sketch technique can be used to detect the attack and it is having the capability of selectively discarding the offending messages only, but not the attack resource. Mainly this can be applied to the VOIP networks, but not to all type of attacks. To prevent DDoS attacks, one of the metrics used is the New Cracking Algorithm. This algorithm includes whenever the client enters into the particular web resource exceeding more than the given threshold, then the client's IP address can be added to the blocked list as an attacker, and the security can be applied by using Message Authentication Code (MAC) for the client's IP address. So this algorithm can protect the web resource even for large volumes of DDoS attack traffic.