Methods, systems, and products are disclosed for detecting an intrusion to a communications network. One embodiment describes a system for detecting intrusions. The system has a peripheral card coupled to a host computer system. The peripheral card has a communications portion and a processor managing the communications portion. The communications portion has only a capability for receiving data packets via a communications network. The communications portion lacks capability of transmitting the data packets via the communications network. The communications portion of the peripheral card reduces intrusion of the communications network.