The invention is a computer system that provides early detection alert and response to electronic threats (eThreats) in large wide area networks, e.g. the network of an Internet Services Provider or a Network Services Provider. The system of the invention accomplishes this by harnessing the processing power of dedicated hardware, software residing in specialized servers, distributed personal computers connected to the network, and the human brain to provide multi-layered early detection, alarm and response. The layers comprise: a Protection Layer, which detects and eliminates from the network data stream eThreats known to the system; a Detection Layer, which detects and creates signatures for new eThreats that are unknown to the system; an Expert Analysis Layer, which comprises a group of human experts who receive information from various components of the system and analyze the information to confirm the identity of new eThreats; and a Collaborative Detection & Protection Layer, which detects potential new eThreats by processing information received from various system agents and users. A Dynamic Sandbox Protection Layer associated with the distributed personal computers connected to the network. can optionally be part of the system of the invention.