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Stinger OC3-ATM Trunk Module Guide
Configuring the OC3-ATM Trunk Module
Checking OC3-ATM trunk interface status
Monitoring errors and performance of the SONET payload
The Performance-Monitoring and Interval-Performance-Monitoring subprofiles include
counters for SONET performance and error conditions.
The Performance-Monitoring values are the cumulative performance counters, which are reset
at the end of every 15-minute interval. The information in the Performance-Monitoring
counters is used to update the values in the Interval-Performance-Monitoring subprofile.
The Interval-Performance-Monitoring values represent performance for the preceding four
15-minute intervals, thereby providing performance data about the past hour.
Events that constitute errors (such as severely errored frames, loss of signal, alarm indication
signal, or STS-path loss of pointer events) are defined in RFC 1595, Definitions of Managed
Objects for the SONET/SDH Interface Type.
Performance and error counters
Performance and error counters are maintained at the section, line, path SONET layers (see
Figure 1-3).
Figure 1-3. SONET layers
As shown in Figure 1-3, a SONET section is a single run of cable. Section-terminating
equipment is any adjacent pair of switches. A line is one or more sections. A path is an
end-to-end circuit.
Coding violations are bit-interleaved parity errors detected in the incoming signal. A severely
errored frame defect begins when four contiguous words are detected with an error in frame
alignment, and ends when two contiguous words occur with error-free frame alignment.
An errored second is a second in which one or more coding violations or incoming errors have
occurred at the specified layer.
A severely errored second is a second in which more than a certain number of coding
violations or incoming errors have occurred, with the number based on line rate and bit error
rate (BER).
Idle-Cell-Counter
Total number of idle cells received.
Valid-Cell-Counter
Total number of valid cells received.
Parameter
Indicates
Path
Line
Section
SONET
