Cisco Systems ONS 15327 Intermediate-Path Performance Monitoring, Section Performance Monitoring

New Features and Functionality

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:

•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.

Release Notes for Cisco ONS 15327 Release 3.3

OL-2671-01 17