Black Box SCAN-LAN VI, Manual

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SCAN-LAN VI
11.2 Viewing Traffic Results
The screen displays a continuous reading of traffic conditions on the
network.
FEATURE DESCRIPTION
One Sec Traffic Shows the average network utilization over the last second.
Average traffic utilization over 30 to 40% indicates a heavily
loaded network.
Peak Traffic The highest one-second average traffic over the duration of the
test.
Collisions Shows the current collisions rate over the last second, expressed
as a percentage of total packets transmitted. Collisions are
counted when runt packets (shorter than a valid minimum packet
length) are detected.
Collision rates exceeding 3% may indicate a faulty station or
network interface card, or an excessively long cable segment.
Last Error Identifies detected transmission errors and the time since the last
error ended in hours, minutes, and seconds.
Error Since Identifies detected transmission errors and the time the error
started in hours, minutes, and seconds.
Bar Graph Displays the current traffic level, scaled from 0 on the left to 50%
on the right side of the display.
Traffic test can detect the following three errors:
ERROR DESCRIPTION
No Link Pulse Indicates that there were no Link pulses received from the
10BASE-T hub, possibly as a result of a faulty hub or cable link
connected to the hub.
Wrong polarity Indicates possible miswire of cable link or hub port caused by
tip/ring reversal on a wire pair.
Jabber Indicates illegal packet length of greater than 20 ms was
received. This suggests a faulty network interface card.