THE DEVICE STATISTICS SCREEN
6-4
Ring Speed (M/bs)
This field displays the ring speed.
6.1.5 Isolating Errors Fields
Isolating Errors are “soft” ring errors that report the domain of a fault (that
is, you can isolate the fault’s region to the transmitting adapter, the
receiving adapter, and the components – cabling and wiring concentrators
– between the two).
A soft error can be recovered through normal operation of the Token Ring
protocol. Although soft errors do not cause ring failure, they degrade
performance of the ring network.
Line Errors
This field displays the total line errors detected by the TRMM/TRMMIM.
These are recorded when a receiving station detects a data corruption in a
packet that was initially transmitted as a good packet. Line errors can be
caused by electronic noise on the ring or by other cable problems. A power
surge may cause the data portion of a frame to be corrupted (i.e., for there
to be a non-valid bit between the data’s start and end delimiters) or a Frame
Check Sequence error.
Since these are isolating, you can use a network management package to
narrow the problem to the station downstream from the error (since the
fault may have occurred as it was receiving) or its upstream neighbor
(since the fault may have occurred as it was transmitting).
Burst Errors
This field displays the total burst errors detected by the
TRMM/TRMMIM. Burst Errors occur when a station’s receiver does not
clock an incoming data signal correctly. These errors normally occur when
there is a brief disruption or electronic surge on the cable, which can
happen when stations enter or leave the ring with no phantom current.
This error can also indicate a problem with the receiver of the reporting
node, or the transmitter of its Nearest Active Upstream Neighbor (NAUN),
or the cabling and hub hardware in between them.