Human-Targeted Denial of Service

Providing live support over the Net is much cheaper than the 1-800 option since an operator can handle several chat sessions simultaneously. The downside of this approach, however, is that “the human in the loop” can now be a target of a new class of network attacks. Take a simple chat-bot program that connects to an online chat service. Smart it is not – an operator can tell it from a human after a few sentences. But that would be too late – the bot has already wasted a few precious minutes of the human assistant’s time at the expense of only a few milliseconds of the attacker’s CPU. And several hundreds of such bots can easily overwhelm the whole team of support operators. In a sense, this makes a semantic Denial of Service (DoS) attack targeted against real people on the Net. We call this attack Human-Targeted Denial of Service, or HTDoS.