Nic Capture Mode - ProfiTap PROFISHARK 1G User Manual

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NIC Capture mode

PROFISHARK transmits network frames to the capture software without
modifying them (see "Feature" chapter). It is transparent for packet size,
packet type or protocols. All tags and encapsulation are preserved (e.g. Vlan,
MPLS, GRE).
The "Software Dropped Packets" counter in the Feature tab indicates the
number of packets dropped by the driver in NIC capture mode. It's not repre-
sentative of the dropped packets in Direct Capture (see "Direct Capture
Mode" chapter). These drop events are caused by too high CPU usage.
The "Hardware Dropped Packets" counter indicates the amount of captured
packets dropped due to low USB bandwidth (e.g. Gigabit capture on USB
2.0). In USB 3.0 mode this counter is not supposed to increase, even in full
speed gigabit capture.
Note: small packet capture at gigabit full speed is extremely challenging for
processors and can cause software drops. For that reason, another capture
mode is available (see "Direct Capture Mode" chapter).