Performance Analysis of Web Service under DDoS Attacks

The essential services such as banking, transportation, medicine, education and defense are being progressively replaced by cheaper and more efficient Internet-based web applications. Therefore, the availability of Web services is very critical for the socio-economic growth of the society. Distributed denial-of-service (DDoS) attacks pose an immense threat to the availability of these services. The services are severely degraded and hence lot of business loses are incurred due to these attacks. To objectively evaluate DDoS attack\´s impact, its severity and the effectiveness of a potential defense, we need precise, quantitative and comprehensive DDoS impact metrics that are applicable to web services. In this paper an attempt has been made to analyze impact of DDoS attacks on the Web services. The experiments are conducted in NS-2. The attack traffic is mixed with legitimate traffic at different strengths and impact of DDoS attacks are measured in terms of throughput, response time, ratio of average serve to request rate, percentage link utilization, and normal packet survival ratio (NPSR). electronic document is a "live" template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.