43,299 research outputs found
An SDN-based Approach For Defending Against Reflective DDoS Attacks
Distributed Reflective Denial of Service (DRDoS) attacks are an immanent
threat to Internet services. The potential scale of such attacks became
apparent in March 2018 when a memcached-based attack peaked at 1.7 Tbps. Novel
services built upon UDP increase the need for automated mitigation mechanisms
that react to attacks without prior knowledge of the actual application
protocols used. With the flexibility that software-defined networks offer, we
developed a new approach for defending against DRDoS attacks; it not only
protects against arbitrary DRDoS attacks but is also transparent for the attack
target and can be used without assistance of the target host operator. The
approach provides a robust mitigation system which is protocol-agnostic and
effective in the defense against DRDoS attacks
Defending against Distributed Denial of Service Attack Under Tunnel Based Forwarding
Today, attacks are a harmful element of the computer networks. Distributed Denial of Service (DDoS) attack is one of the most harmful attacks. Many defense mechanisms have been proposed to mitigate the effect of the attacks. 2In this thesis, we study two methods for defending against DDoS attacks.
First, we identify the attack packets to detect a DDoS attack by checking the TTL value of incoming packets and monitoring the number of new source IP addresses of incoming packets. Second, we propose an algorithm to traceback the attack traffic to identify the source IP address of origin by deploying a tunneling based protocol.
The tunneling based protocol is called the Locator/Identifier Separation Protocol (LISP) and it is deployed in a domain network to encapsulate all outgoing packets decapsulate all incoming packets. As a side-effect the tunneling protocol reveals the ingress point of attack traffic.
We also analyzed the approach in a simulation environment and compare the results in the domain network when deploying the tunneling based protocol
Implementing Pushback: Router-Based Defense Against DDoS Attacks
Pushback is a mechanism for defending against distributed denial-of-service (DDoS) attacks. DDoS attacks are treated as a congestion-control problem, but because most such congestion is caused by malicious hosts not obeying traditional end-to-end congestion control, the problem must be handled by the routers. Functionality is added to each router to detect and preferentially drop packets that probably belong to an attack. Upstream routers are also notified to drop such packets (hence the term Pushback) in order that the router's resources be used to route legitimate traffic. In this paper we present an architecture for Pushback, its implementation under FreeBSD, and suggestions for how such a system can be implemented in core routers
Experimental evaluation of select servers and firewalls under denial of service security attacks
Internet security requires newer prevention mechanisms to be implemented on web-servers and routers. Firewall/Intrusion Prevention mechanisms (IPS) can be deployed on host servers or routers as an added line of defense against Internet attacks. In this thesis, we evaluate performance of security mechanisms provided by these devices against Distributed Denial of Service (DDoS) attacks. The host based firewalls on Windows servers-2003 and 2008 were evaluated. In this thesis, we also evaluated Juniper Networks Netscreen-5GT firewall/IPS, and Cisco ASA-5510/IPS that are used in protecting web-servers against DDoS attacks. It was found that the host based firewalls and protection mechanisms on the windows servers were not capable of defending against the DDoS attacks. Our performance evaluation showed the computing resource of the servers to be completely exhausted under these attacks. The evaluation of firewalls and IPS under different loads of attack had varying performance in supporting the number of web connections
Defending Against Denial of Service
Civil Society currently faces significant cyber threats. At the top of the list of those threats are Denial of Service (DoS) attacks. The websites of many organizations and individuals have already come under such attacks, and the frequency of those attacks are on the rise. Civil Society frequently does not have the kinds of resources or technical know-how that is available to commercial enterprise and government websites, and often have to exist in adverse political environments where every avenue available, both legal and illegal, is used against them. Therefore, the threat of DoS attacks is unlikely to go away any time soon.A Denial of Service (DoS) attack is any attack that overwhelms a website, causing the content normally provided by that website to no longer be available to regular visitors of the website. Distributed Denial of Service (DDoS) attacks are traffic volumebased attacks originating from a large number of computers, which are usually compromised workstations. These workstations, known as 'zombies', form a widely distributed attack network called a 'botnet'. While many modern Denial of Service attacks are Distributed Denial of Service attacks, this is certainly not true for all denials of service experienced by websites. Therefore, when users first start experiencing difficulty in getting to the website content, it should not be assumed that the site is under a DDoS attack. Many forms of DoS are far easier to implement than DDoS, and so these attacks are still used by parties with malicious intent. Many such DoS attacks are easier to defend against once the mechanism used to cause the denial of service is known. Therefore, it is paramount to do proper analysis of attack traffic when a site becomes unable to perform its normal function. There are two parts to this guide. The first part outlines preparatory steps that can be taken by Civil Society organizations to improve their website's resilience, should it come under attack. However, we do understand that most Civil Society organizations' first introduction to DoS attacks comes when they suddenly find themselves the victim of an attack. The second part of this guide provides a step-by-step process to assist the staff of NGOs to efficiently deal with that stressful situation
Preventing DDoS using Bloom Filter: A Survey
Distributed Denial-of-Service (DDoS) is a menace for service provider and
prominent issue in network security. Defeating or defending the DDoS is a prime
challenge. DDoS make a service unavailable for a certain time. This phenomenon
harms the service providers, and hence, loss of business revenue. Therefore,
DDoS is a grand challenge to defeat. There are numerous mechanism to defend
DDoS, however, this paper surveys the deployment of Bloom Filter in defending a
DDoS attack. The Bloom Filter is a probabilistic data structure for membership
query that returns either true or false. Bloom Filter uses tiny memory to store
information of large data. Therefore, packet information is stored in Bloom
Filter to defend and defeat DDoS. This paper presents a survey on DDoS
defending technique using Bloom Filter.Comment: 9 pages, 1 figure. This article is accepted for publication in EAI
Endorsed Transactions on Scalable Information System
- …