Denial of Service (DoS) or Distributed-Denial of Service (DDoS) is major threat to network security. Network is collection of nodes that interconnect with each other for exchange the Information. This information is required for that node is kept confidentially. Attacker in network computer captures this information that is confidential and misuse the network. Hence security is one of the major...

A Distributed Denial of Service (DDoS) attack is a major security threat for networks and Internet services. Attackers can generate attack traffic similar to normal network traffic using sophisticated attacking tools. In such a situation, many intrusion detection systems fail to identify DDoS attack in real time. However, DDoS attack traffic behaves differently from legitimate network traffic i...

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 environ...

In this paper, we are going to present the simulation results of comparison of five queuing algorithms (Drop Tail, Fair Queuing, Stochastic Fair Queuing, Deficit Round Robin and Random Early Detection) using ns-2 as simulation environment. Comparison of the queuing algorithms is based on attack-intensity. We are checking the performance of each queuing algorithm on a particular queue limit agai...

Distributed Denial of Service (DDoS) attacks are security attacks that prevent normal use of communication facilities. More and more DDoS attacks are occurring each day. Conventional DDoS attacks are typically based on flooding the server. Currently, other types of DDoS attacks have been observed, such as the mimicry DDoS attack. The mimicry attack is characterized by (1) gradual increase in th...

In this paper, we present a study on the recent approaches in handling Distributed Denial of Service (DDoS) attacks. DDoS attack is a fairly new type of attack to cripple the availability of Internet services and resources. A DDos attack can originate from anywhere in the network and typically overwhelms the victim server by sending a huge number of packets. Several remedial measures have been ...

In recent years, distributed denial of service (DDoS) attacks have become a major security threat to Internet services. How to detect and defend against DDoS attacks is currently a hot topic in both industry and academia. In this paper, we propose a novel framework to robustly and efficiently detect DDoS attacks and identify attack packets. The key idea of our framework is to exploit spatial an...

Distributed Denial-of-Service (DDoS) attacks are a variant of Denial-of-Service (DoS) attacks where an attacker or a group of attackers employ multiple machines to carry out a DoS attack simultaneously, therefore increasing its effectiveness and strength. DDoS attacks in the networks needs to be prevented or handled if it occurs, as early as possible and before reaching the victim. Dealing with...

We present a new class of low-volume application layer DDoS attack–Very Short Intermittent DDoS (VSI-DDoS). Such attack sends intermittent bursts (tens of milliseconds duration) of legitimate HTTP requests to the target website with the goal of degrading the quality of service (QoS) of the system and damaging the long-term business of the service provider. VSI-DDoS attacks can be especially ste...

Distributed Denial-of-Service attack (DDoS) is one of the most outstanding menaces on the Internet. A DDoS attack generally attempts to overwhelm the victim in order to deny their services to legitimate users. A number of approaches have been proposed for defending against DDoS attacks accurately in real time. However, existing schemes have limits in terms of detection accuracy and delay if the...