Denial of service attacks:Dos attacks

Denial of service attack(DOS) is one of the most basic attack which can be done against any network. In this attack we flood the network or web server with different legitimate looking requests an the legitimate user is unable to access the service. There are various types of denial of service attack depending on the type of request used. A distributed denial of service attack is a denial of service attack in which the web server or the network is flooded by different attackers at the same time so that the network or web server crashes(party play).

How to?
There are various ways and tools to perform a denial of service attack.

1. The most basic way to perform an denial of service attack with and windows machine is by typing in the command ping ip -t -l 19000 here -t is for delay time of the packets and -l is for the length of the packet. But this method is outdated and hence the magnitude required to crash is very high. You can consider this as the method your grandfather will use to attack the networks which are of his age and are still being used without any alterations. 
   
2. The second way to attack is by using the famous LOIC. Low Orbit Ion Cannon is an open source stress testing tool which has a GUI. It is easy to use as you only need to set the URL or ip and then hit lock on then you can change the settings as per your requirements and then just hit fire. This tool is available in both windows as well as android. According to some rumors the famous hacktivist group "Anonymous" use this tool in most of their attacks.
3. There are various tools in Kali Linux to perform such attacks but the best way is by using the command flood_router6 interface where interface can be eth0 or any other interface if your target is using an windows regular or server version lower than 8. We haven't tested this on higher versions so we don't know how it may react against this attack.
   
4. To attack a router with a SYN dos attack you can use the tool present in msfconsole. Just type use auxiliary/dos/tcp/synflood. Now type set rhost ip to set the ip of the host machine. At the end type exploit to start the exploitation.

Note:- 
These attacks can be easily detected by intrusion detection system which might block the specific port or alert the system admin.  This attack is often exaggerated by the media but is very weak against large setups.