ZyWALL 10 Internet Security Gateway

 

11.2

Call Control Support ................................................................................................................

11-2

11.2.1

Budget Management.........................................................................................................

11-2

11.2.2

Call History ......................................................................................................................

11-3

11.3

Time and Date Setting..............................................................................................................

11-4

How often does the ZyWALL update the time?...............................................................................

11-6

11.4

Remote Management Setup......................................................................................................

11-7

11.5

Boot Commands .......................................................................................................................

11-8

Chapter 12 Telnet Configuration and Capabilities .............................................................................

12-1

12.1

About Telnet Configuration......................................................................................................

12-1

12.2

Telnet Under NAT....................................................................................................................

12-1

12.3

Telnet Capabilities....................................................................................................................

12-1

12.3.1

Single Administrator ........................................................................................................

12-1

12.3.2

System Timeout................................................................................................................

12-2

12.4

Telnet Behind the Firewall .......................................................................................................

12-2

Firewall and Content Filters .........................................................................................................................

13-1

Chapter 13 What is a Firewall? ............................................................................................................

13-1

13.1

Types of Firewalls ....................................................................................................................

13-1

13.1.1

Packet Filtering Firewalls.................................................................................................

13-1

13.1.2

Application-level Firewalls ..............................................................................................

13-1

13.1.3

Stateful Inspection Firewalls ............................................................................................

13-2

13.2

Introduction to ZyXEL’s Firewall............................................................................................

13-2

13.3

Denial of Service ......................................................................................................................

13-3

13.3.1

Basics................................................................................................................................

13-3

13.3.2 Types of DoS attacks........................................................................................................

13-4

13.4

Stateful Inspection....................................................................................................................

13-6

13.4.1

Stateful Inspection Process...............................................................................................

13-7

13.4.2 Stateful Inspection & the ZyWALL .................................................................................

13-8

13.4.3

TCP Security ....................................................................................................................

13-8

13.4.4

UDP/ICMP Security.........................................................................................................

13-9

13.4.5

Upper Layer Protocols......................................................................................................

13-9

13.5

Guidelines For Enhancing Security With Your Firewall..........................................................

13-9

13.5.1

Security In General.........................................................................................................

13-10

Chapter 14 Introducing the ZyWALL Firewall ..................................................................................

14-1

Table of Contents

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