A team at the University of Washington wants to marshal swarms of good computers to neutralize the bad ones. They say their plan would be cheap to implement and could cope with botnets of any size.

To shield the protected server, their system, called Phalanx, uses a large network of computers, such as content distribution networks. Instead of the server being accessed directly, all information must pass through the swarm of “mailbox” computers, which slows down botnet attacks.

The mailboxes do not simply relay information to the server like a funnel — they only pass on information when the server requests it. That allows the server to work at its own pace, without being swamped.