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Método de mitigação contra ataques de negação de serviço distribuídos utilizando sistemas multiagentes.; Method for mitigating against distributed denial of service attacks using multi-agent system.

Pereira, João Paulo Aragão
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/07/2014 Português
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A qualidade do serviço oferecido por Provedores do Serviço de Internet (Internet Service Provider - ISPs) depende diretamente da quantidade de recursos disponíveis naquele momento. Nas últimas décadas, essa qualidade tem sido afetada por frequentes e intensos ataques que consomem tais recursos, como é o caso dos ataques de Negação de Serviço Distribuídos (Distributed Denial of Service - DDoS). Com o objetivo de tornar a rede dos ISPs mais resiliente aos diferentes tipos de ataques DDoS, foram desenvolvidas técnicas contra tais ataques ao longo dos últimos anos. Com o objetivo de contribuir com a melhoria de tais mecanismos, esta dissertação apresenta um método autônomo reativo para detecção e mitigação de ataques DDoS, utilizando um sistema multiagentes (SMA), em redes de ISPs. A propriedade principal do método proposto é identificar padrões de tráfego característicos de um ataque, como um grande fluxo de pacotes direcionados para um serviço ou equipamento, dentro da rede do ISP. Com os agentes posicionados nas prováveis vítimas e nos pontos da rede com maior fluxo de pacotes, o processo de mitigação inicia-se automaticamente após uma quantidade de pacotes, excedente ao tráfego padrão, passar por qualquer um dos nós monitorados. Como o tráfego entrante na rede do ISP é dinâmico...

An approach to mitigate denial of service attacks in ieee 802.11 networks

Ribeiro, Adriano Cesar; Pinto, Alex Sandro Roschildt; Zafalon, Geraldo Francisco Donega; Pigatto, Daniel Fernando; Branco, Kalinka Castelo; Cansian, Adriano Mauro
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 128-137
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Wireless networks are widely deployed and have many uses, for example in critical embedded systems. The applications of this kind of network meets the common needs of most embedded systems and addressing the particularities of each scenario, such as limitations of computing resources and energy supply. Problems such as denial of service attacks are common place and cause great inconvenience. Thus, this study presents simulations of denial of service attacks on 802.11 wireless networks using the network simulator OMNeT++. Furthermore, we present an approach to mitigate such attack, obtaining significant results for improving wireless networks.

Denial of service mitigation approach for IPv6-enabled smart object networks

Oliveira, Luís Miguel Lopes; Rodrigues, Joel; Sousa, Amaro Fernandes de; Lloret, Jaime
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
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Denial of service (DoS) attacks can be defined as any third-party action aiming to reduce or eliminate a network’s capability to perform its expected functions. Although there are several standard techniques in traditional computing that mitigate the impact of some of the most common DoS attacks, this still remains a very important open problem to the network security community. DoS attacks are even more troublesome in smart object networks because of two main reasons. First, these devices cannot support the computational overhead required to implement many of the typical counterattack strategies. Second, low traffic rates are enough to drain sensors’ battery energy making the network inoperable in short times. To realize the Internet of Things vision, it is necessary to integrate the smart objects into the Internet. This integration is considered an exceptional opportunity for Internet growth but, also, a security threat, because more attacks, including DoS, can be conducted. For these reasons, the prevention of DoS attacks is considered a hot topic in the wireless sensor networks scientific community. In this paper, an approach based on 6LowPAN neighbor discovery protocol is proposed to mitigate DoS attacks initiated from the Internet...

Distributing network identity to mitigate denial-of-service attacks

Naresh, Pallavi
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 81 p.
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The CONTRA. Camouflage of Network Traffic to Resist Attacks, project was carried out by Draper Laboratory to provide a defense mechanism against distributed denial of service (DDoS) attacks to both prevent DDoS attacks and mitigate their effects. This Masters project looks at the CONTRA system and assesses its effectiveness. The goal of this project is to explore whether the techniques employed by CONTRA-nalnely IP dispersion. redundancy, and traffic masking, can effectively mitigate the effects of a DDoS attack. The analysis provides a set of recommendations for operating the CONTRA system to impede an outside attacker.; by Pallavi Naresh.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.; Includes bibliographical references.

The electronic revolution: is the nation state redundant?

Broome, John
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 97919 bytes; 356 bytes; application/pdf; application/octet-stream
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[Introduction]: Today much of our daily business involves the use of the Internet and, through it, electronic commerce or e-commerce. We buy products and pay bills over the net. We access information for work, pleasure or to satisfy our curiosity. We have the ability to communicate with friends and colleagues across the city or across the world instantaneously. We have the ability to conduct research without ever visiting a library. But the revolution in life-style and work for each of us as individuals has been matched or exceeded by the changes this electronic revolution has brought to every sector of the business community. Massive changes in areas such as health, education and entertainment are also occurring. But what if it all suddenly stopped? What if the Australian Stock Exchange went off line for a day or even longer? What if the banks, most of whose business customers and a growing number of individual customers use and rely on line services, were shut down by a denial of service attack? What if the credit card systems were shut down and ATMs unable to function for a significant period? The result would be chaotic and the cost immense. A denial of service attack involves the sending of many messages to a site at the same time with the effect that the system is effectively ‘jammed’. If the perpetrator of what is a premeditated ‘terrorist’ attack on the target site decided to repeat the attack at various intervals (and from different locations) the disruption could be maintained for a significant period. Because of the nature of e-commerce the site must be accessible to the public and other businesses so a change of site name is no solution. Business would come to a standstill. In Australia the ASX is susceptible to a denial of service attack now that both brokers and individual traders rely on the net to do business. Such an attack would not only cost millions in lost business it may seriously affect the value of the dollar. If a number of financial institutions were targeted at once it would further exacerbate the apparent perception that the Australian economy is old world rather than new. That perception is often cited as the reason for the continued fall in the value of the Australian dollar. In short we would face an economic catastrophe. It is ironic that the extent to which Australia has adopted electronic commerce makes it so vulnerable. Such an attack would...

Mitigating distributed denial of service attacks with Multiprotocol Label Switching--Traffic Engineering (MPLS-TE)

Vordos, Ioannis
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado
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Approved for public release, distribution unlimited.; A Denial of Service (DoS) occurs when legitimate users are prevented from using a service over a computer network. A Distributed Denial of Service (DDoS) attack is a more serious form of DoS in which an attacker uses the combined power of many hosts to flood and exhaust the networking or computing resources of a target server. In recent years, DDoS attacks have become a major threat to both civilian and military networks. Multi-Protocol Label Switching with Traffic Engineering (MPLS-TE) is an emerging technology that allows explicit, bandwidth-guaranteed packet forwarding paths to be established for different traffic flows. It provides a means for diverting packets of a suspected DDoS attack for analysis and cleaning before forwarding them to the actual destination. The objective of this research was to implement and evaluate the performance of an MPLS-TE based solution against DDoS attacks on a realistic test-bed network consisting of Cisco routers. The test-bed has been integrated with Snort®, an open source Intrusion Detection System (IDS), to achieve automatic detection and to mitigate DDoS attacks. The test-bed network was subject to a series of malicious traffic flows with varying degrees of intensity. The results demonstrated that MPLS-TE is very effective in mitigating such attacks. The overall system response time and the router CPU loads are comparable to those reported by two former NPS theses that examined alternative solutions based on BGP blackhole routing.

Defending IEEE 802.11-based networks against denial of service attacks

Tan, Boon Hwed
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xiv, 117 p. : ill. (some col.)
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Approved for public release, distribution is unlimited; The convenience of IEEE 802.11-based wireless access networks has led to widespread deployment in the consumer, industrial and military sectors. However, this use is predicated on an implicit assumption of confidentiality and availability. In addition to widely publicized security flaws in IEEE 802.11's basic confidentially mechanisms, the threats to network availability presents any equal, if not greater danger to users of IEEE 802.11-based networks. It has been successfully demonstrated that IEEE 802.11 is highly susceptible to malicious denial-of-service (DoS) attacks targeting its management and media access protocols. Computer simulation models have proven to be effective tools in the study of cause and effect in numerous fields. This thesis involved the design and implementation of a IEEE 802.11-based simulation model using OMNeT++, to investigate the effects of different types of DoS attacks on a IEEE 802.11 network, and the effectiveness of corresponding countermeasures.; Major, Republic of Singapore Navy

Toward an internet service provider (ISP) centric security

Price, Patrick D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xi, 78 p. : ill. (some col.), col. map ;
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Approved for public release; distribution is unlimited; This thesis was completed in cooperation with the Institute for Information Superiority and Innovation.; Individual users, businesses, and governments have become functionally dependent on the Internet's connectivity to interact at the most basic levels of social and economic intercourse. Yet self-propagating worms and distributed denial of service attacks have demonstrated that disruption of the Internet infrastructure can be quickly achieved despite the vast knowledge of vulnerabilities and readily available subscriber-based countermeasures. In part, this condition is made possible because networks continue to operate under an obsolete subscriber-centric security paradigm that is based on all end users being trusted to act appropriately. This thesis develops the idea of an Internet Service Provider (ISP)- centric security approach by examining the types, roles, security mechanisms, and operational precepts of ISP's to illustrate their functional control within the infrastructure. Denial of service and worm attacks are detailed to provide the context for an emerging set of conditions that forms the basis of the requirement for the ISP approach. This paper concludes by examining four enabling technologies currently available that...

A method for mitigating denial of service attacks on differentiated services networks

Braun, Matthew J.
Fonte: Monterey, California: Naval Postgraduate School, 2002. Publicador: Monterey, California: Naval Postgraduate School, 2002.
Formato: xiv, 85 p. : ill. (some col.) ; 28 cm.
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Approved for public release; distribution is unlimited; This thesis presents a method for countering Denial of Service (DoS) attacks in networks that provide Quality of Service (QoS) guarantees using Differentiated Service (DiffServ). This approach uses feedback from the DiffServ provider to initiate packet signing at the source. The signature allows the DiffServ provider to distinguish valid packets from malicious packets. This mechanism can also be used to provide key management for other digital signature methods, such as the Internet Protocol Authentication Header (IP AH). However, unlike other methods, our solution requires no encryption or cryptographic processing on a per-packet basis. Instead, it utilizes the sender's ability to alter its packet signatures faster than the attacker can duplicate the changes. This method also avoids the fragmentation and decreased throughput associated with increased packet size of IP AH through use of existing fields in the IP header. This method results in a significant reduction in valid packets that are dropped during a DoS attack. Thus, a DiffServ provider would be able to maintain QoS guarantees during an attack without incurring the overhead associated with cryptographic signatures. A C++ implementation of this DoS countermeasure for the ns2 network simulator and the experimental simulation scripts are included as appendices.; Lieutenant...

Stateful anycast for distributed DDoS mitigation; Stateful anycast for distributed denial-of-service mitigation

Hansen, Richard E., M. Eng. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 103 p.
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Distributed denial-of-service (DDoS) attacks can easily cripple victim hosts or networks, yet effective defenses remain elusive. Normal anycast can be used to force the diffusion of attack traffic over a group of several hosts to increase the difficulty of saturating resources at or near any one of the hosts. However, because a packet sent to the anycast group may be delivered to any member, anycast does not support protocols that require a group member to maintain state (such as TCP). This makes anycast impractical for most applications of interest. This document describes the design of Stateful Anycast, a conceptual anycast-like network service based on IP anycast. Stateful Anycast is designed to support stateful sessions without losing anycast's ability to defend against DDoS attacks. Stateful Anycast employs a set of anycasted proxies to direct packets to the proper stateholder. These proxies provide DDoS protection by dropping a session's packets upon group member request. Stateful Anycast is incrementally deployable and can scale to support many groups.; by Richard E. Hansen.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 97-103).

A Novel Protective Framework for Defeating HTTP-Based Denial of Service and Distributed Denial of Service Attacks

Saleh, Mohammed A.; Abdul Manaf, Azizah
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
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The growth of web technology has brought convenience to our life, since it has become the most important communication channel. However, now this merit is threatened by complicated network-based attacks, such as denial of service (DoS) and distributed denial of service (DDoS) attacks. Despite many researchers' efforts, no optimal solution that addresses all sorts of HTTP DoS/DDoS attacks is on offer. Therefore, this research aims to fix this gap by designing an alternative solution called a flexible, collaborative, multilayer, DDoS prevention framework (FCMDPF). The innovative design of the FCMDPF framework handles all aspects of HTTP-based DoS/DDoS attacks through the following three subsequent framework's schemes (layers). Firstly, an outer blocking (OB) scheme blocks attacking IP source if it is listed on the black list table. Secondly, the service traceback oriented architecture (STBOA) scheme is to validate whether the incoming request is launched by a human or by an automated tool. Then, it traces back the true attacking IP source. Thirdly, the flexible advanced entropy based (FAEB) scheme is to eliminate high rate DDoS (HR-DDoS) and flash crowd (FC) attacks. Compared to the previous researches, our framework's design provides an efficient protection for web applications against all sorts of DoS/DDoS attacks.

HoneyMesh: Preventing Distributed Denial of Service Attacks using Virtualized Honeypots

Deshpande, Hrishikesh Arun
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/08/2015 Português
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Today, internet and web services have become an inseparable part of our lives. Hence, ensuring continuous availability of service has become imperative to the success of any organization. But these services are often hampered by constant threats from myriad types of attacks. One such attack is called distributed denial of service attack that results in issues ranging from temporary slowdown of servers to complete non-availability of service. Honeypot, which is a sort of a trap, can be used to interact with potential attackers to deflect, detect or prevent such attacks and ensure continuous availability of service. This paper gives insights into the problems posed by distributed denial of service attacks, existing solutions that use honeypots and how a mesh of virtualized honeypots can be used to prevent distributed denial of service attacks.; Comment: 5 Pages with 4 figures and 1 table

Denial of Service Attack: Analysis of Network Traffic Anormaly using Queuing Theory

Singh, Neetu; Ghrera, S. P.; Chaudhuri, Pranay
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/06/2010 Português
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Denial-of-service (DOS) attacks increasingly gained reputation over the past few years. As the Internet becomes more ubiquitous, the threat of the denial-of-service attacks becomes more realistic and important for individuals, businesses, governmental organizations, and even countries. There is intensive need to detect an attack in progress as soon as possible. The efficiency of diagnosing the DOS attack using concepts of queuing theory and performance parameter of the system has been investigated in the present work, as the servers definitely have some mechanisms to store and process the requests. Utilizing this concept of queuing theory, the collection of data patterns were generated. With the performance parameter of the system, the analysis of the data pattern had been made to diagnose the network anomaly. Performance analysis and results show the accuracy of the proposed scheme in detecting anomalies.; Comment: Submitted to Journal of Computer Science and Engineering, see http://sites.google.com/site/jcseuk/volume-1-issue-1-may-2010

A Framework for Hybrid Systems with Denial-of-Service Security Attack

Wang, Shuling; Nielson, Flemming; Nielson, Hanne Riis
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Hybrid systems are integrations of discrete computation and continuous physical evolution. The physical components of such systems introduce safety requirements, the achievement of which asks for the correct monitoring and control from the discrete controllers. However, due to denial-of-service security attack, the expected information from the controllers is not received and as a consequence the physical systems may fail to behave as expected. This paper proposes a formal framework for expressing denial-of-service security attack in hybrid systems. As a virtue, a physical system is able to plan for reasonable behavior in case the ideal control fails due to unreliable communication, in such a way that the safety of the system upon denial-of-service is still guaranteed. In the context of the modeling language, we develop an inference system for verifying safety of hybrid systems, without putting any assumptions on how the environments behave. Based on the inference system, we implement an interactive theorem prover and have applied it to check an example taken from train control system.; Comment: 19 pages, 1 figures, the short version was accepted by FORTE 2014

An Efficient Detection Mechanism for Distributed Denial of Service (DDoS) Attack

Kumarasamy, Saravanan; Asokan, Dr. R.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/02/2013 Português
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Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks have emerged as a popular means of causing collection particular overhaul disruptions, often for total periods of instance. The relative ease and low costs of initiation such attacks, supplemented by the present insufficient sate of any feasible defense method, have made them one of the top threats to the Internet centre of population nowadays. Since the rising attractiveness of web-based applications has led to quite a lot of significant services being provided more than the Internet, it is very important to monitor the network transfer so as to stop hateful attackers from depleting the assets of the network and denying services to rightful users. The most important drawbacks of the presently existing defense mechanisms and propose a new-fangled mechanism for defending a web-server against a DDoS attack. In the proposed mechanism, incoming traffic to the server is always monitored and some irregular rise in the inbound traffic is without delay detected. The detection algorithm is based on a statistical analysis of the inbound traffic on the server and a robust suggestion testing structure. While the detection procedure is on, the sessions from the rightful sources are not disrupted and the load on the server is restored to the usual level by overcrowding the traffic from the attacking sources. The accurate modules employ multifaceted detection logic and hence involve additional overhead for their execution. On the other hand...

Business and social evaluation of denial of service attacks of communications networks in view of scaling economic counter-measures

Pau, L. -F.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 13/08/2013 Português
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This paper gives an analytical method to determine the economic and indirect implications of denial of service and distributed denial of service attacks. It is based on time preference dynamics applied to the monetary mass for the restoration of capabilities, on long term investments to rebuild capabilities, and of the usability level of the capabilities after an attack. A simple illustrative example is provided for a denial of service on a corporate data centre. The needed data collection methodologies are categorized by classes of targets. The use of the method is explained in the context of legal or policy driven dissuasive, retaliation or compensation/ restoration actions. A concrete set of deployment cases in mobile communications services is discussed. The conclusion includes policy recommendations as well as information exchange requirements.

Exploring the provision of online booter services

Hutchings, Alice; Clayton, Richard
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Article; accepted version
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This is the author accepted manuscript. It is currently embargoed pending publication.; This research uses differential association, techniques of neutralisation and rational choice theory to study those who operate ?booter services?: websites that illegally offer denial-of-service attacks for a fee. Booter services provide ?easy money? for the young males that run them. The operators claim they provide legitimate services for network testing, despite acknowledging that their services are used to attack other targets. Booter services are advertised through the online communities where the skills are learnt and definitions favourable towards offending are shared. Some financial services proactively frustrate the provision of booter services, by closing the accounts used for receiving payments.; The work would not have been possible without the invaluable assistance of Ross Anderson. It was supported by the Department of Homeland Security (DHS) Science and Technology Directorate, Cyber Security Division (DHSS&T/CSD) Broad Agency Announcement 11.02, the Government of Australia and SPAWAR Systems Center Pacific [contract number N66001-13-C-0131]. The opinions, findings, and conclusions or recommendations expressed are those of the authors and do not reflect those of the aforementioned agencies.

Mitigating Denial-of-Service Flooding Attacks with Source Authentication

Liu, Xin
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2012 Português
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Denial-of-Service (DoS) flooding attacks have become a serious threat to the reliability of the Internet. For instance, a report published by Arbor Networks reveals that the largest DoS flooding attack observed in 2010 reaches 100Gbps in attack traffic volume. The defense against DoS flooding attacks is significantly complicated by the fact that the Internet lacks accountability at the network layer: it is very difficult, if not impossible, for the receiver of an IP packet to associate the packet with its real sender, as the sender is free to craft any part of the packet.

This dissertation proposes to mitigate DoS flooding attacks with a two-step process: first to establish accountability at the network layer, and second to utilize the accountability to efficiently and scalably mitigate the attacks. It proposes Passport, a source authentication system that enables any router forwarding a packet to cryptographically verify the source Autonomous System (AS) of the packet. Passport uses symmetric key cryptography to enable high-speed verification and piggy-backs its key exchange into the inter-domain routing system for efficiency and independence from non-routing infrastructures.

On top of Passport, this dissertation proposes NetFence...

NAT denial of service: An Analysis of translation table behavior on multiple platforms

Winemiller, Nathan
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
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Network Address Translation or NAT, is a technology that is used to translate internal addresses to globally routable addresses on the internet. It is used extensively in almost every network requiring global connectivity due to the current lack of IPv4 addresses. The primary mechanism used to facilitate the translation of internal addresses to external addresses and vice versa is the translation table. This study takes an in-depth look at how five different vendors: Cisco, Extreme, Linksys, VMWare, and Vyatta, implement the translation table during active NAT sessions. Additionally, this study analyzes the methodology required to fill a translation table and the Denial of Service that is a result of the attack. We consider the relative difficulty of accomplishing this task between the different platforms and protocols (TCP vs UDP vs ICMP). We conclude this study with steps that can be taken to prevent or mitigate the NAT DOS attack.

NAT Denial of Service: An Analysis of Translation Table Behavior on Multiple Platforms

Winemiller, Nathan; Hartpence, Bruce; Johnson, Daryl; Mishra, Sumita
Fonte: The 2012 International Conference on Security and Management Publicador: The 2012 International Conference on Security and Management
Tipo: Conference Proceeding
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Network Address Translation or NAT, is a technology that is used to translate internal addresses to globally routable addresses on the internet. NAT continues to be used extensively in almost every network due to the current lack of IPv4 addresses. Despite being exceptionally commonplace, this networking technique is not without its weaknesses, and can be disabled with a fairly straightforward attack. By overpopulating the translation table, the primary mechanism used to translate the internal to external addresses, an attacker can effectively deny all internal users access to the external network. This paper takes an in-depth look at how five different vendors: Cisco, Extreme, Linksys, VMWare, and Vyatta, implement the translation table during active NAT sessions and how they are affected by TCP, UDP, and ICMP variations of the DOS attack.