Installation guide

McAfee® Network Security Platform 6.0 How dongles work
Again, the relays come into play when the Sensor is powered off:
Figure 8: Mechanical Relay - Fail closed
Because the relays only pass the signals on pins 1, 2, 3, and 6, however, the transmit
signals on pins 4 and 5 are filtered out and the ports fail closed.
So what does the dongle do? The answer becomes obvious when we compare the Sensor
port pin-outs configured for fail-closed operation to standard Ethernet cable pin-outs:
Figure 9: Pin-out comparison
As the previous diagram indicates, a Sensor in fail-closed mode uses pins 4 and 5 to
transmit signals, yet standard 10/100 Ethernet connections use pins 1 and 2 to transmit
signals (pins 4 and 5 are not used). Without a mechanism to transpose the signals, traffic
therefore comes to a halt.
Note: The operating mode of the Sensor has no effect on the receive (Rx) signals,
so they are not shown here for simplicity.
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