Essay on IT Security

TCP SYN Flood : A SYN flood attack works by not responding to the server with the expected ACK code.

To reduce the risk of these types of attacks, routers should be hardened, packet filtering controls should be used and routing information should be controlled.

A malicious node can impersonate or spoof the address of another node in order to alter the vision of the network topology as perceived by another node. Such attacks can result in the formation of loops as described below [18]

The Internet Security Association and Key Management Protocol(ISAKMP) is a protocol framework that defines payload formats, themechanics of implementing a key exchange protocol, and thenegotiation of a security association.

Denial-of-Service attack (DoS) when a hacker continuously attacks a particular network or dedicated Access Point (AP) with fake requests, failure messages and premature successful connection messages and other commands. These causes authorized users from preventing connecting to the network and results in network failure or crash. These attacks depends on misuse of protocols like Extensible Authentication Protocol (EAP).

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

A DoS Attack, or Denial-of-Service attack, is an attack that that fill a network with lots of useless traffic. Many DoS attacks, such as the Ping of Death and Teardrop attacks, exploit limitations in the TCP/IP protocols. A couple of the most recent DoS attacks have been directed to Capitol One and SunTrust Banks. In October Capital One and SunTrust were attacked by this Denial-of-Service. Capital One’s website was inaccessible for 8 hours because the network was just filled with useless traffic. In the next couple of days SunTrust bank suffered performance issues.

To mitigate the security threat posed by ping sweeps and port scans it is highly recommended that firewall protection on all network hosts devices should be enabled to close any unused ports to protect them from unauthorized access. Also, is recommended that the use of a firewall server to protect the network from any outside intruders be used as well.

What are Denial-of-service attacks? According to the Homeland Security's website, it is an attack that prevents the user from accessing information or services, usually by overwhelming the system. "By targeting your computer and its network connection, or the computers and network of the sites you are trying to use, an attacker may be able to prevent you from accessing email, websites, online accounts (banking, etc.), or other services that rely on the affected computer." (McDowell) A distributed denial-of-service attack uses a main host to infect and overwhelm other computers on the same network. Of course, there is no way to completely prevent an attack, but there are ways to reduce the change of getting these attacks. Some good habits are to keep the anti-virus software updated, install a firewall, and to have strong email spam filters. Additionally, regularly keeping backups of important files is always a good idea. If a user falls under this attack, they can contact a DOS Specialist or contact the appropriate Internet Service

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 recipient of a message using a digital certificate can obtain the public key associated with that particular certificate and then decode the message and verify that it did indeed originate from the proper source. With this information, the recipient is then able to send an encrypted reply.

known as an intrusion prevention system (IPS). auto-responds to the suspicious activity by resetting the connection. reprogramming the firewall to block network traffic from the suspected malicious source. IDPS is commonly used automatically at the command of an operator; systems that both "detect" (alert) and/or "prevent."

A denial-of-service attack (DoS attack)/distributed denial-of-service attack (DDoS attack) is an attempt of making a computer resource unavailable to its intended users.

Distributed denial of service is hard to block. Due to much traffic, system could not tolerate the unacceptable requests from different machines. A single user is attacked from the number of attackers. The millions of requests force the computer to shut down. The main purpose of denial of service is to disturb business of specific organization. The normal work is effected such as make server unavailable to its regular users. A single blockage of an IP address could not stop the attack.