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Layer 2 loopback: Filters out broadcast, multicast and null
DA (destination address) packets of incoming data streams,
and then resends the rest of incoming data streams back to
the same connected port with swapped DA/SA (destination/
source MAC address) and recalculated CRC.
Gigabit ethernet
Gigabit Ethernet (GbE or 1 GigE) is a term that transmits
Ethernet frames at a rate of a gigabit per second. GIGATEST
is a Gigabit packets generator and network test equipment.
CRC error
At the tail of a frame/packet, it keeps a checksum value to
verify the integrity of the frame when it is received. If the
checksum value is not correct that can verify the correctness
of the frame, we call it CRC Error frame. Poor network
transmission can cause this kind of error. GIGATEST is able
to detect this kind of error and show result after test.
