3Com LINKBUILDER 3C18500, User Manual

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P P E N D I X
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T H E R N E T
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T A T I S T I C S
DUA1850-0AAA05
addressed to all MAC addresses (that is, all devices) on the network.
The total number of broadcast frames will normally be a small
percentage of the value seen for unicast frames. A high level of
broadcast frames can adversely affect network performance.
Data Rate Mismatches. The number of frames received by the
repeater, module or port whose timing was outside the permitted
frequency range. This may indicate non-compliant or faulty devices
on your network.
Errors/10000 Packets . The number of total errors per 10,000 packets
received by the repeater, module or port. This statistic gives an
indication of the general health of the network.
FCS Errors . Frame Check Sequence (FCS) errors indicate that frames
of data are being corrupted. FCS errors are counted when incoming
frames fail the Cyclic Redundancy Check (CRC) test. The number of
FCS errors should be a very small percentage of the total data
traffic.
Check the transceiver or adapter card of the device connected to
the port that is the source of the problem. If the card appears to be
operating correctly, check the cable and cable connections for
breaks or damage. Occasionally the problem may be caused by
interference from other cables or machinery.
Good Frames . This is the total number of frames with no errors seen
by the repeater, module or port. Examining this statistic regularly
can help you monitor your network's overall performance. Look for
unusual increases in traffic rate. This may indicate a potential
problem, or help you decide if a bridge is required on your network.
Good Octets . This field shows the total number of octets (bytes)
received as part of good frames seen at the repeater, module or
port. The total includes the header, data and CRC octets of each
frame. The Good Octets value allows you to calculate the
throughput, in terms of bytes per second, and the average frame
size on your network.