A Red Team is defined by Kelly Sheridan on the DarkReading blog as “A group of people within an organization responsible for, well, attacking it. Their goal is to act like the adversary and figure out different ways to break into a company so it can strengthen its defenses.”
Kelly continues with a discussion of red and blue teaming so that, when you’ve completed reading it, you’ll have a full-out introduction to a sensible in-house strategy for defeating computer hackers. You start with the organizational setting you are seeking to protect.
“A red team needs at least two people to be effective, though many range from two to five.” And on from there.