RESCUE: Reputation based Service for Cloud User Environment

Exceptional characteristics of Cloud computing has replaced all traditional computing. With reduced resource management and without in-advance investment, it has been victorious in making the IT world to migrate towards it. Microsoft announced its office package as Cloud, which can prevent people moving from Windows to Linux. As this drift is escalating in an exponential rate, the cloud environment has become a good target for attackers also. Hence as to get the best use of the cloud services, the security issues have to be dealt with first. Among various security threats faced by the cloud environment, we are focusing here on the most dangerous of all, Distributed Denial of Service Attack, DDoS. In DDoS attack, a victim is targeted simultaneously by numerous hosts distributed across the network. An attacker compromises the vulnerable systems in the network and infects those systems with malicious code which can trigger these systems, called zombies, to send requests in huge numbers to choke the target. This type of attack can happen both at network as well as service level. In this paper, a three phase authentication scheme, REputation based Service for Cloud User Environment  has been proposed that can help the Cloud Service Provider to detect and mitigate both the aforesaid types of DDoS attacks. RESCUE, the proposed scheme authenticates the users in three different phases. Puzzle solving is used to discriminate human beings and robots. Based on the traffic flow, in case of network level attack and the interval between the consequent service requests,in case of service level attack, users are authenticated Credits are given to users based on this authentication and services are provisioned accordingly.