Networking and Communication Engineering

R. Rathika ¹, M. Ambika ²

Affiliations
1 PRIST University, Vallam, Thanjavur, IN
2 P.R. Engineering College, Vallam, Thanjavur, IN

Abstract

Customer Relationship Management, is an area where cloud computing can really shine. Applications for CRM can help a business organize and track its contacts with customers. Thus knowledge discovery and management plays vital role in these area. In this article we propose a new approach for automatic learning of terminological ontologies from text corpus based on probabilistic topic models .In our approach topic models are used as efficient dimension reduction techniques, which are able to capture semantic relationships between word-topic and topic-document interpreted in terms of probability distributions. This article proposed a method to create and handle ontology object model. The work has also involve testing the performance of the proposed algorithm. Thus compared to manual approaches, the automated building of ontology has the advantages of fast development, cost effectiveness, and being resistant to obsolescence.

Keywords

Cloud Computing, Web Ontology, Ontology Generation, Probabilistic Topic Models, CRM.

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R. Rathika ¹, B. Dharanya ², K. Kiruthika Devi ³

Affiliations
1 Sri Ramakrishna Engineering College, Coimbatore-22, IN
2 Sri Ramakrishna Engineering College, Coimbatore -22, IN
3 Sri Ramakrishna Engineering College, Coimbatore-22, IN

Abstract

Distributed Denial of Service (DDoS) attacks is flattering ever more challenging with the vast resources and techniques increasingly available to attackers. Distributed Denial of Service (DDoS) attacks constitutes one of the most important threats and among the hardest security problems in today's Internet of particular concern are Distributed Denial of Service (DDoS) attacks, whose collision can be proportionally severe. In this paper, consider sophisticated attacks that are protocol-compliant, non-intrusive, and utilize legitimate application-layer requests to overwhelm system resources. I have characterize application-layer resource attacks as either request flooding, asymmetric, or repeated one-shot, on the basis of the application workload parameters that they exploit. To protect servers from these attacks, propose a counter-mechanism that consists of a suspicion assignment mechanism and a DDoS-resilient scheduler, DDoS Shield. In contrast to prior work, our distrust mechanism assigns a continuous valued vs. binary measure to each client session, and the scheduler utilizes these values to determine if and when to schedule a session’s requests. Using tested experiments on a web application, demonstrate the strength of these resource attacks and evaluate the efficiency of our counter-mechanism. For instance, affect an asymmetric attack which overwhelms the server resources, increasing the response time of legitimate clients from 0.1 seconds to 10 seconds. Under the same attack scenario, DDoS Shield limits the effects of false-negatives and false-positives and improves the victims’ performance to 0.8 seconds.

Keywords

Distributed Denial of Service Attack (DDos), Web Application, Application Layer.

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R. Tamil Selvi , R. Rathika

Abstract

Distributed Denial of Service (DDoS) attacks constitutes one of the most important threats and among the hardest security problems in today's Internet of particular concern are Distributed Denial of Service (DDoS) attacks, whose collision can be proportionally severe. A distributed denial of service (DDoS) attack is designed to overpower victims with traffic and put off their network resources from working correctly for their legitimate clients. Recently, there have been an increasing numbers of DDoS attacks against online services and Web applications.  The most common form of DDoS attacks is a packet-flooding attack, in which a large number of apparently legitimate TCP, User Datagram Protocol (UDP) or Internet Control Message Protocol (ICMP) packets are directed to a specific destination. With small or no prior warning, a DDoS attack can easily fatigue the computing and communication resources of its victim within a short period of time. Because of the seriousness of the problem many defense mechanisms have been proposed to conflict these attacks. This paper presents a survey of various DDoS attacks enforced on web applications as well as online services. Moreover, the paper also provides an outline of various defense mechanisms proposed earlier to counter the DDoS attacks. This paper also presents some fundamental ideas to design and develop a system that better handles the DDoS attacks.

Keywords

Bandwidth, Distributed Denial of Service (DDoS) Attacks, Traffic Flow, Network Security, and Web Applications.

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