Contents

Preface

 

Purpose ...........................................................................................................................

xv

Audience ..........................................................................................................................

xv

Conventions .....................................................................................................................

xvi

Special Message Formats .........................................................................................

xvi

Use of Enter, Type, and Press ...................................................................................

xvi

Other Conventions ...................................................................................................

xvii

Related Publications .......................................................................................................

xvii

Chapter 1

 

Introduction

 

About the Router ............................................................................................................

1-1

Features .........................................................................................................................

1-1

Key Features ............................................................................................................

1-2

ISDN Support ...........................................................................................................

1-3

Multilink PPP Support ..............................................................................................

1-3

TCP/IP Support ........................................................................................................

1-4

IP Address Masquerading by Dynamic NAT+ ....................................................

1-4

Automatic Configuration of Attached PCs by DHCP .........................................

1-4

Security ....................................................................................................................

1-4

Calling Line Identification ...................................................................................

1-4

PAP and CHAP Authentication ..........................................................................

1-5

Callback .............................................................................................................

1-5

Management Support ..............................................................................................

1-5

Basic Router Concepts ...................................................................................................

1-6

What is a Router? ....................................................................................................

1-6

Routing Information Protocol ....................................................................................

1-6

IP Addresses and the Internet .................................................................................

1-7

Netmask ...................................................................................................................

1-9

Contents

v