Cisco ASR 900 Series Configuration Guide

An STS-3 frame is nine rows by 270 bytes. The first nine columns contain the transport overhead section,
and the rest is SPE. For both STS-3 and STS-3c, the transport overhead (Line and Section) is the same.
For an STS-3 frame, the SPE contains three separate payloads and three separate path overhead fields. In
essence, it is the SPE of three separate STS-1s packed together, one after another.
For more information on Section Overhead, Line Overhead, and Path Overhead, refer the following:
•
http://www.cisco.com/c/en/us/support/docs/optical/synchronous-digital-hierarchy-sdh/5462-sdh-overview.html
•
http://www.cisco.com/c/en/us/support/docs/optical/synchronous-optical-network-sonet/13567-sonet-tech-tips.html
•
http://www.cisco.com/c/en/us/tech/optical/synchronous-optical-network-sonet/tsd-technology-support-troubleshooting-technotes-list.html
SONET Line and Section Configuration Parameters
The following parameters affect SONET configuration at the line and section levels:
• Overhead — Sets the SONET overhead bytes in the frame header to a specific standards requirement,
or to ensure interoperability with equipment from another vendors.
• J0 — Sets the J0 or C1 byte value in the SONET section overhead.
1 byte, 16 bytes, and 64 bytes are the supported values for J0.Note
• S1S0 — Sets the SS bits value of the H1 byte in the SONET line overhead.
• Loopback — Sets a loopback to test the SONET port.
• AIS-Shut — Configures the SONET port to send the Alarm Indication Signal (AIS) at shutdown.
• Shut — Disables an interface.
• Alarm Reporting — Enables reporting for all or selected alarms.
• lias —Enables line alarm indication signal.
• lrdi — Enables line remote defect indication signal.
• pais — Enables path alarm indication signal.
• plop — Enables loss of pointer failure signal for a path.
• pplm — Enables path payload mismatch indication.
• prdi — Enables path remote defect indication signal.
• sd-ber — Sets Signal Degrade BER threshold.
• Clock — Specifies the clock source, where:
• line —The link uses the recovered clock from the line.
• internal — The link uses the internal clock source. This is the default setting.
1-Port OC-192 or 8-Port Low Rate CEM Interface Module Configuration Guide, Cisco IOS XE Everest 16.7.x
(Cisco ASR 900 Series)
24
Configuring SONET
SONET Line and Section Configuration Parameters

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English