Source Network Tap Card

I need a network TAP card that is less expensive and works as well as my existing source (Dualcomm). These look like ethernet NIC cards and work somewhat the same, but they have a special feature in that they pass the data from one NIC to the other automatically and passively (and they must also pass a copy of the data to a device. Also look for a device that has dual NIC ports to a USB connection. The critical features for a Tap card: 1) Input port for network connection 2) Output port for network connection 3) Passive pass-through from input to output so network traffic remains unaffected 4) Works at minimum of 100Mbps - 1T capability is better 5) Has NIC port(s) to send copied packets to computer or direct connection to PC bus 6) Continues to operate pass-through even if host PC is not working These are the critical elements of dual NIC to USB: 1) Two NIC ports operating at minimum of 100 Mbps 2) One USB connector, preferably 2.0 3) Input from NICs converted to USB, traveling different channels through USB (USB can handle multiple channels, as in the way USB hubs work).