A network tap for enabling attached devices, such as an intrusion detection system, to transmit information into a communication line of the network without disrupting the network traffic on the communication line. When the attached device is an intrusion detection device, the network tap is connected to a firewall. An Ethernet switch or field programmable gate array (FPGA) is incorporated in the network tap to coordinate the transmission of device data to avoid data collisions with data transmissions already existing in the communication line. The network tap may be operated in various modes to accommodate different capabilities of attached devices. In addition, the network tap has various port configurations to allow a user to connect various attached devices through a single cable or dual cables.