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isco Synchronous Digital Hierarchy (SDH) Graphical Ove


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Table of ContentsSynchronous Digital Hierarchy (SDH) Graphical Overview..........................................................................1

Introduction.............................................................................................................................................1

Before You Begin...................................................................................................................................1

Conventions...............................................................................................................................1

Prerequisites...............................................................................................................................1

Components Used..................... .................................................................................................1

SDH Analysis.........................................................................................................................................1

The SDH Link............................................................................................................................2

STM1 Frames............................................................................................................................2

STM1 SOH................................................................................................................................2

VC4 Concatenation....................................................................................................................3

SDH Hierarchy..........................................................................................................................3

SDH Maintenance Interactions..................................................................................................4

Alarms and Detection Criteria...................................................................................................4

STM1 SOH, HOPOH and LOPOH Bytes.............................................................................5

Related Information..............................................................................................................................12

Cisco Synchronous Digital Hierarchy (SDH) Graphical Overview

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Synchronous Digital Hierarchy (SDH) GraphicalOverview

Introduction

Before You Begin

Conventions

PrerequisitesComponents Used

SDH Analysis

The SDH Link

STM1 Frames

STM1 SOH

VC4 Concatenation

SDH Hierarchy

SDH Maintenance Interactions

Alarms and Detection Criteria

STM1 SOH, HOPOH and LOPOH Bytes

Related Information

Introduction

This document provides an overview of Synchronous Digital Hierarchy (SDH) represented in images.

Before You Begin

Conventions

For more information on document conventions, see the Cisco Technical Tips Conventions.

Prerequisites

There are no specific prerequisites for this document.

Components Used

This document is not restricted to specific software and hardware versions.

The information presented in this document was created from devices in a specific lab environment. All of the

devices used in this document started with a cleared (default) configuration. If you are working in a livenetwork, ensure that you understand the potential impact of any command before using it.

SDH Analysis

The sections below provide an overview of SDH in graphical format.



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The SDH Link

The diagram below shows what an SDH link looks like.

STM1 Frames

The diagram below shows the Synchronous Transport Module level 1 (STM1) frame structure.

STM1 SOH

The diagram below shows what the STM1 Section Overhead (SOH) looks like.



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VC4 Concatenation

The diagram below looks at VC4 Concatenation.

SDH Hierarchy

The diagram below displays the SDH hierarchy.



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SDH Maintenance Interactions

The diagram below shows how SDH maintenance interactions look.

Alarms and Detection Criteria

The table below looks at what the alarms mean and their detection criteria.



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STM1 SOH, HOPOH and LOPOH Bytes

The diagrams below provide a description of all the bytes from STM1 SOH, High Order Path Overhead

(HOPOH)and Low Order Path Overhead (LOPOH) .



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Related Information

Technical Support Cisco Systems

Tools and Utilities Cisco Systems

Optical Product Support Pages

All contents are Copyright 19922002 Cisco Systems, Inc. All rights reserved. Important Notices and Privacy Statement.

Updated: Dec 13, 2002 Document ID: 28327


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