Another device we will most likely encounter is the switch. Since a switch is a unicast device and only floods all ports with broadcast traffic, when we are up against one, we want to try and create a situation where the switch will either forward packets incorrectly to the wrong destination that we hope is us or get the switch to flood all information out all ports, in effect becoming a hub.
The attacks we want to look at are called layer two attacks. While it is true that there are switches that operate all the way up to layer seven of the Open System Interconnect (OSI) model, we will focus on the more traditional approach that operates at layer two.
For a number of years, we enjoyed the luxury of being able to flood a switch using an excellent tool known as macof. You can read more about it at http://linux.die.net/man/8/macof. You may still have some success with the macof tool, but it usually only works when you encounter a switch that is from before the year 2006....