Fddi Macs; Setting The Frame Error Threshold; Setting The Not Copied Threshold - 3Com corebuilder 3500 Implementation Manual

106 C 6: F
HAPTER IBER

FDDI MACs

Setting the Frame
Error Threshold
Setting the Not
Copied Threshold
D D I
ISTRIBUTED ATA NTERFACE
You can display MAC statistics and configure the following parameters:
MAC FrameErrorThreshold
NotCopiedThreshold
Logical Link Control (LLC) service
The FrameErrorThreshold attribute determines when the system
generates a MAC condition report because too many frame errors have
occurred. A frame error occurs when a frame becomes corrupted.
Station Management (SMT) monitors the ratio of frame errors to all
frames that are transmitted within a certain period of time. The
FrameErrorThreshold setting determines at what percentage the frame
errors are significant enough to report to network management. The
threshold value is expressed in a percentage based on 65536 (which is
100 percent). For example, to set the threshold at 1 percent, the value is
655 (the system default). The lower that you set the percentage, the
more likely it is for SMT to report a problem.
Effects and Consequences
When you set the frame error threshold, consider the following:
A high error rate often indicates a faulty station on the FDDI ring or a
dirty FDDI connector.
The NotCopiedThreshold attribute determines when the system
generates a MAC condition report because too many frames could not be
copied. Not-copied frames occur when there is no buffer space available
in the station (which in turn indicates congestion in the station).
SMT monitors the ratio of frames that are not copied to all frames that
are transmitted within a certain period of time. The NotCopiedThreshold
setting determines at what percentage the number of frames that are not
copied is significant enough to report to network management. The
threshold value is expressed in a percentage based on 65536 (which is
100 percent). For example, to set the threshold at 1 percent, the value is
655 (the system default). The lower that you set the percentage, the
more likely it is for SMT to report a problem.
(FDDI)