LOIC is very easy DoS tool available but at the same time very effective. Lets take a look at how easy it is to lunch an attack with this tool. For this LAB we will use windows 7 system with LOIC installed and Linux system running tcpdump. The victim system will have IP address 192.168.0.102 and the system from which we will lunch the attack will be 192.168.0.90

1. On windows 7 system download LOIC from https://sourceforge.net/projects/loic/
You may need download and install .net 4.0 in case you get an error message

2. Start LOIC.exe
loic1
3. Under select your target, select 192.168.0.102. Select TCP Port 80 with 10000 threads. Ones completed start the attack.
loic2
4. Start tcpdump on port 80 on 192.168.0.102 system and you can watch your attack.

08:00:16.351566 IP 192.168.0.89.49929 > on.local.http: Flags [S], seq 3460445827, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
08:00:16.351598 IP on.local.http > 192.168.0.89.49929: Flags [R.], seq 0, ack 3460445828, win 0, length 0
08:00:16.372019 IP 192.168.0.89.49914 > on.local.http: Flags [S], seq 1172867234, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
08:00:16.372050 IP on.local.http > 192.168.0.89.49914: Flags [R.], seq 0, ack 1, win 0, length 0
08:00:16.372070 IP 192.168.0.89.49915 > on.local.http: Flags [S], seq 2790229765, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
08:00:16.372078 IP 192.168.0.89.49916 > on.local.http: Flags [S], seq 1536137593, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
08:00:16.372099 IP on.local.http > 192.168.0.89.49915: Flags [R.], seq 0, ack 1, win 0, length 0
08:00:16.372107 IP on.local.http > 192.168.0.89.49916: Flags [R.], seq 0, ack 1, win 0, length 0
08:00:16.403313 IP 192.168.0.89.49917 > on.local.http: Flags [S], seq 3436438582, win 8192, options [mss 1460,nop,wscale 8,nop,nop,sackOK], length 0
08:00:16.403344 IP on.local.http > 192.168.0.89.49917: Flags [R.], seq 0, ack 1, win 0, length 0