Table of Contents:

Definition and Overview

1. Transport Network Role

2. Multiplexing

3. Asynchronous Hierarchy: Comparison with SONET

4. Types of Network Elements

5. SONET Hierarchy

6. Structure to Carry Data

7. SONET Network Architecture

8. When Is a Separate SONET Layer Needed?

Self-Test

Glossary

PDF of this tutorial

ADM
add/drop multiplexer

ANSI
American National Standards Institute

ATM
asynchronous transfer mode

DCS
digital cross-connect

MUX
multiplexer

OC
optical carrier

PABX
private automatic branch exchange

SDH
synchronous digital hierarchy

SONET
synchronous optical network

SPE
synchronous payload envelope

STS
synchronous transport signal

TDM
time division multiplexing

VC
virtual container

VT
virtual tributary