Go to this website and read the information regarding Carnivore.

http://computer.howstuffworks.com/carnivore.html

Provide a couple of paragraphs answering the question on the first page:

What exactly was Carnivore? Where did it come from? How did it work? What was its purpose?

Also provide perspective on the impact of this software, in light of the time, what is warranted? Was it an overreach by the government?