ICTACT Journal on Communication Technology

S. Seetha ¹, P. Raviraj ¹

Affiliations
1 Department of Information Technology, Karunya University, Coimbatore, Tamil Nadu, IN

Abstract

Distributed Denial of service is a major threat to the availability of internet services. Due to the distributed, large scale nature of the Internet makes DDoS (Distributed Denial-of-Service) attacks stealthy and difficult to counter. Defense against Distributed Denial- of - Service attacks is one of the hardest security problems on the Internet. Recently these network attacks have been increasing. Therefore more effective countermeasures are required to counter the threat. This requirement has motivated us to propose a novel mechanism against DDoS attack. This paper presents the design details of a distributed defense mechanism against DDoS attack. In our approach, the egress routers of the intermediate network coordinate with each other to provide the information necessary to detect and respond to the attack. Thus, a detection system based on single site will have either high positive or high negative rates. Unlike the traditional IDSs (Intrusion Detection System) this method has the potential to achieve high true positive ratio. This work has been done by using consensus algorithms for exchanging the information between the detection systems. So the overall detection time would be reduced for global decision making.

Keywords

DDoS Attack, IDSs, Consensus Algorithm.

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C. Shanmuganathan ¹, P. Raviraj ²

Affiliations
1 Department of Computer Science and Engineering, Manonmaniam Sundaranar University, IN
2 Department of Computer Science and Engineering, GSSS Institute of Engineering and Technology for Women, IN

Abstract

A Mobile Ad hoc Network (MANET) is a collection of autonomous nodes or mobile devices that can arrange themselves in various ways and work without strict network administration. Ensuring security in mobile ad hoc networks is a challenging issue and most of the applications in mobile ad hoc networks involve group oriented communication. Mostly cryptographic techniques are used to provide the security to MANETs. Cryptographic techniques will not be efficient security mechanism if the key management is weak. The issue of packet loss in MANET that is caused due to multi casting and backward and forward secrecy results in mobility. Hence, we investigate on this issue and propose a method to overcome this scenario. On analysing the situation we find that frequent rekeying leads to huge message overhead and hence increases energy utilization. With the existing key management techniques it causes frequent disconnections and mobility issues. Therefore, an efficient multi casting group key management will help to overcome the above problems. In this paper we propose a novel group key rekeying technique named GPRKEY (Group key with Periodic ReKEYing) deal with scalability issue of rekeying and also analyze the performance of the newly proposed key management method using key trees. In this approach we use the periodic rekeying to enhance the scalability and avoid out of sync problems. We use sub trees and combine them using the merging algorithm and periodic re-keying algorithm. The GPRKEY is evaluated through NS-2 simulation and compared with existing key management techniques OFT (One-way Function Tree) and LKH (Logical Key Hierarchy). The security and performance of rekeying protocols are analyzed through detailed study and simulation.

Keywords

Mobile Ad Hoc Networks, Periodic, Security, Rekey, Sub Tree.

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