Denial Of Service ( Dos )

The big item in the news lately from a cyber security standpoint has been Distributed Denial of Service (DDoS) attacks, their frequency and size being the two big sticking points for the media. The one thing that the media tends not to do is explain what a DDoS is, what attack vector was used, realistically all the information that leads to a clear picture of what really happened during the attack. With that this paper will explain the process from beginning to end of a DDoS attack in a way that is easy to understand and hopefully debunks a lot of the misconceptions about DDoS that have been posted in class discussion.

This Denial of Service (DoS) intrusion event started unfolding as the clinic’s users of the internet started to experience such slowness in connecting to systems that they were unable to perform their jobs. This lack of

Imagine that you get home from a hard day at work or school, have a bite to eat, and then sit at your computer. After you've checked your e-mail, you're ready to play an online game. Excitement begins to build, but then you notice your browser was denied access to your network, preventing you from connecting to the Internet. In desperation, you turn your computer's power off and restart it. After the reboot, your computer still cannot reach any networked service. Since only your computer was involved, you think it may be a Denial of Service attack. However, days later you learn that the attack you experienced was a Distributed Denial of Service, an attack involving numerous computers that flooded the game servers and prevented anyone from gaining

(Samuel Folledo) How many of us know exactly what Denial-of-Service attacks is? Aside from how powerful and easy it is to perform these attacks, its mysteriousness alone illustrates a huge danger in the computer world. A deep understanding of DoS can save a lot of headaches as these cybercriminals are able to steal from personal informations to bringing down sites and companies. The first wall of prevention against these attacks is always awareness. This is why being knowledgeable on Denial-of-Service attacks important. (End of Intro)

Denial of service cyberattacks are attacks on websites that make them inaccessible to normal people. While a lot of cyberattacks are used to steal information, denial of service attacks don’t try to. Instead, they try to make website servers unavailable and in some cases, they are “used as a smokescreen for other malicious activities,” like trying to take down firewalls. A successful denial of service attack impacts a very large number of people, so hackers and other people like to use this to send messages to the public. Denial of Service attacks can last for months; this makes them very dangerous for online businesses. They make companies lose money and customers and inconvenience everyday users. These reasons are

Threat: Denial of Service is the interruption of service on a device that prevents legitimate users from accessing it. A common source of this type of attack is from malicious agents. This is a threat because of the importance of the server to this small investigation business. Since this is where clients upload their evidence, it must always perform at its optimal capability. With this in mind denial of service attacks becomes a great threat, as the opposing party in a case will benefit from evidence not being not being uploaded to the attorneys (OWASP Top 10, 2015).

A Denial-of-Service (DoS) attack is a general name for any kind of attack against data availability. In the Web application world, a DoS attack aims to “take down” the site in order to make it inaccessible to its users. This may cause some serious financial damage to the site, both directly and indirectly by damaging its reputation.

Denial of Service (DoS) attack is a very common cyber menace that renders websites and other online means inaccessible to intended users. There are various types of DoS threats and nearly all directly target the core server structure. Others abuse weaknesses in application and communication proprieties. DoS is also used as a cover-up for other wicked actions, and to take down security applications like web firewalls. A prosperous DoS attack is very obvious and impacts the entire online user base.

Denial of Service attack (DoS attack) are attacks making the computer unusable and the programs unavailable as systems flood a user’s bandwidth Historically, a computer system is overloaded with false requests and data, causing the system to go into shock and crash. The multiple attacks from different IP addresses, sometimes thousands, making it hard for the computer to pinpoint the source. Used in large and layered networks, using multi-threaded OSI layered attacks and a pre-scanned reconnaissance usually disguised as legitimate traffic, the malware infiltrates databases and destroys resources. Causing the unavailability of websites and/or dramatically slow processing. The first known use of DoS attack was done by Khan Smith in 1997,

The three main access control methods available are Mandatory Access Control (MAC), Discretionary Access Control (DAC) and Role-Based Access Control (RBAC). Each one of these control methods provides different layers or levels of technical controls that will limit an IT system or network user’s access to data based on security access controls. Mandatory Access Control is a security model where users are given permissions to resources (files, folders or documents) by an administrator (Windows OS) or root (LINUX or UNIX OS) user. The configuration changes to the file or resource permissions can only be modified by the authorized system administrator. Discretionary Access Control is a security model where users

Role based access control is an ideology through which access to systems is restricted based on authority given. It is used by organizations with a relatively large number of employees ranging from five hundred to one thousand and above (Sieunarine & University of Oxford, 2011). This is implemented through the mandatory access control or through the discretionary access control. These are the only two ways through which role based access control can be implemented.

Demonstration of different types of DDoS attacks in a simulated virtual environment. We have chosen examples from each type of DDoS attack namely volume based attacks (UDP flood, TCP flood, ICMP flood), protocol based attacks (SYN flood) and application level attacks (HTTP). We used network stress testing tools like Low Orbit Ion Cannon (LOIC), Hping3 to simulate these DDos attacks from multiple virtual machines. In addition, we have portrayed ways to detect these attacks.

Role based access control (RBAC) is the real trick of making standard levels of access "consents" to the different figuring assets and systems of an association that are customized to particular representative parts, or employment works as opposed to people. In an expansive, data escalated association, it is for the most part far simpler and more solid for framework security administrators to allocate another contract to one or more "parts" and have all the proper authorizations set naturally than to do every physicaly.

The primary objective of a network security system is to, in a cost effective manner, balance convenient access to legitimate users and inaccessibility to attackers. In a nutshell, the goal is to prevent connectivity to anyone intending to cause harm to the network. The harm to which this paper refers can come in the following forms:

Now that we have broken down the various types of DoS attacks there is one very important unanswered question; how can these attacks be prevented? The