Cisco ONS 15327 Manual page 17

Intermediate-Path Performance Monitoring
Release 3.3 supports Intermediate-Path Performance Monitoring (IPPM), which is the transparent
monitoring of a constituent channel of an incoming transmission signal by a node that does not terminate
that channel. IPPM allows you to monitor near-end PM data on individual STS payloads and report the
associated threshold crossing alerts (TCAs) for user-selected STS payloads passing through a Cisco
ONS 15327 OC-N card. Far-end PM monitoring is not presently supported.
An ONS 15327 performing IPPM examines the overhead in the monitored path and derives all of the
near-end PM parameters in the incoming transmission direction while allowing the path signal to pass
bidirectionally through the NE completely unaltered.
IPPM parameters are derived as follows: a bidirectional path is cross-connected through the ONS 15327
(non-PTE equipped) and has path terminations at path terminating equipment (PTE) 1 and PTE 2. Four
sets of PM parameters are accumulated when IPPM is activated. For the path signal received on facility
1, these include the near-end parameters monitored on the path from PTE 1 to the SONET Line
Terminating Equipment (LTE). For the path signal received on facility 2, these include the near-end
parameters.
Intermediate J1 and C2 Monitor and Report
Release 3.3 provides intermediate monitoring of the SONET J1 and C2 bytes, which means the LTE NE
can provide on-demand diagnostics to detect and report the contents of the STS Path Trace and Signal
Label in non-terminated STS Paths designated by the user. The J1 Byte contains a repetitive 64-byte
message used to verify continuity between STS PTEs transmitting the byte. The J1 byte reports when an
expected 64-byte message is not received. The C2 Signal Label byte provides a similar functionality. The
C2 byte contains binary values or codes that define a specific type of payload transmitted in the STS
SPE. The C2 byte is provisioned at the PTE. It is used to both identify the SPE payload and support STS
Payload Defect Indication (PDI-P). Release 3.3 allows you to monitor these bytes at intermediate (LTE)
nodes and monitor specific STS Paths. You can provision an expected J1 or C2 value so that the node
reports when an expected value for either byte is not received at the intermediate node.
Section Performance Monitoring
The SONET Section PM feature enables the Cisco ONS 15327 to accumulate and report the section layer
performance monitoring parameters on any OC-N card. The section layer deals with the transport of an
STS-N frame across the physical medium. This layer handles framing, scrambling, and error monitoring.
All types of SONET devices terminate the section layer. A SONET regenerator, however does not
process beyond the physical and section layers. When a non-Cisco regenerator is used on the span
between two ONS 15327s operating as LTEs, the ONS 15327 Section PM isolates the side of the
regenerator that is causing any bit errors.
The ONS 15327 monitors the following section-layer parameters:
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OL-2671-01
Severely Errored Framing Seconds (SEFS-S): the number of seconds an SEF defect was present
Errored Seconds (ES-S): the number of seconds during which at least 1 section BIP error was
detected, or an SEF or LOS defect was present.
Severely Errored Seconds (SES-S): the number of sections during which K or higher section BIP
errors were detected or an SES or LOF was present (K is bit-rate dependent).
Coding Violations (CV-S): a count of the number of section-layer BIP errors.
New Features and Functionality
Release Notes for Cisco ONS 15327 Release 3.3
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