ZyXEL Communications Internet Security Appliance ZyWALL5UTM 4.0 User manual

ZyWALL 5/35/70 Series
Internet Security Appliance
User’s Guide
Version 4.00
10/2005

ZyWALL 5/35/70 Series User’s Guide
Copyright 2
Copyright
Copyright © 2005 by ZyXEL Communications Corporation.
The contents of this publication may not be reproduced in any part or as a whole, transcribed,
stored in a retrieval system, translated into any language, or transmitted in any form or by any
means, electronic, mechanical, magnetic, optical, chemical, photocopying, manual, or
otherwise, without the prior written permission of ZyXEL Communications Corporation.
Published by ZyXEL Communications Corporation. All rights reserved.
Disclaimer
ZyXEL does not assume any liability arising out of the application or use of any products, or
software described herein. Neither does it convey any license under its patent rights nor the
patent rights of others. ZyXEL further reserves the right to make changes in any products
described herein without notice. This publication is subject to change without notice.
Trademarks
ZyNOS (ZyXEL Network Operating System) is a registered trademark of ZyXEL
Communications, Inc. Other trademarks mentioned in this publication are used for
identification purposes only and may be properties of their respective owners.

ZyWALL 5/35/70 Series User’s Guide
3 Federal Communications Commission (FCC) Interference Statement
Federal Communications
Commission (FCC) Interference
Statement
This device complies with Part 15 of FCC rules. Operation is subject to the following two
conditions:
• This device may not cause harmful interference.
• This device must accept any interference received, including interference that may cause
undesired operations.
This equipment has been tested and found to comply with the limits for a Class B digital
device pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference in a commercial environment. This equipment
generates, uses, and can radiate radio frequency energy, and if not installed and used in
accordance with the instructions, may cause harmful interference to radio communications.
If this equipment does cause harmful interference to radio/television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and the receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver
is connected.
• Consult the dealer or an experienced radio/TV technician for help.
Notice 1
Changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equipment.
This Class B digital apparatus complies with Canadian ICES-003.
Cet appareil numérique de la classe B est conforme à la norme NMB-003 du Canada.
Certifications
1Go to www.zyxel.com.
2Select your product from the drop-down list box on the ZyXEL home page to go to that
product's page.
3Select the certification you wish to view from this page.

ZyWALL 5/35/70 Series User’s Guide
Federal Communications Commission (FCC) Interference Statement 4

ZyWALL 5/35/70 Series User’s Guide
5 Safety Warnings
Safety Warnings
For your safety, be sure to read and follow all warning notices and instructions.
• Do NOT open the device or unit. Opening or removing covers can expose you to
dangerous high voltage points or other risks. ONLY qualified service personnel can
service the device. Please contact your vendor for further information.
• Connect the power cord to the right supply voltage (110V AC in North America or 230V
AC in Europe).
• Place connecting cables carefully so that no one will step on them or stumble over them.
Do NOT allow anything to rest on the power cord and do NOT locate the product where
anyone can walk on the power cord.
• If you wall mount your device, make sure that no electrical, gas or water pipes will be
damaged.
• Do NOT install nor use your device during a thunderstorm. There may be a remote risk of
electric shock from lightning.
• Do NOT expose your device to dampness, dust or corrosive liquids.
• Do NOT use this product near water, for example, in a wet basement or near a swimming
pool.
• Make sure to connect the cables to the correct ports.
• Do NOT obstruct the device ventilation slots, as insufficient airflow may harm your
device.
• Do NOT store things on the device.
• Connect ONLY suitable accessories to the device.

ZyWALL 5/35/70 Series User’s Guide
ZyXEL Limited Warranty 6
ZyXEL Limited Warranty
ZyXEL warrants to the original end user (purchaser) that this product is free from any defects
in materials or workmanship for a period of up to two years from the date of purchase. During
the warranty period, and upon proof of purchase, should the product have indications of failure
due to faulty workmanship and/or materials, ZyXEL will, at its discretion, repair or replace the
defective products or components without charge for either parts or labor, and to whatever
extent it shall deem necessary to restore the product or components to proper operating
condition. Any replacement will consist of a new or re-manufactured functionally equivalent
product of equal value, and will be solely at the discretion of ZyXEL. This warranty shall not
apply if the product is modified, misused, tampered with, damaged by an act of God, or
subjected to abnormal working conditions.
Note
Repair or replacement, as provided under this warranty, is the exclusive remedy of the
purchaser. This warranty is in lieu of all other warranties, express or implied, including any
implied warranty of merchantability or fitness for a particular use or purpose. ZyXEL shall in
no event be held liable for indirect or consequential damages of any kind of character to the
purchaser.
To obtain the services of this warranty, contact ZyXEL's Service Center for your Return
Material Authorization number (RMA). Products must be returned Postage Prepaid. It is
recommended that the unit be insured when shipped. Any returned products without proof of
purchase or those with an out-dated warranty will be repaired or replaced (at the discretion of
ZyXEL) and the customer will be billed for parts and labor. All repaired or replaced products
will be shipped by ZyXEL to the corresponding return address, Postage Paid. This warranty
gives you specific legal rights, and you may also have other rights that vary from country to
country.

ZyWALL 5/35/70 Series User’s Guide
7 Customer Support
Customer Support
Please have the following information ready when you contact customer support.
• Product model and serial number.
• Warranty Information.
• Date that you received your device.
• Brief description of the problem and the steps you took to solve it.
METHOD
LOCATION
SUPPORT E-MAIL TELEPHONEAWEB SITE
REGULAR MAIL
SALES E-MAIL FAX FTP SITE
CORPORATE
HEADQUARTERS
(WORLDWIDE)
[email protected] [phone] www.zyxel.com
www.europe.zyxel.com
ZyXEL Communications Corp.
6 Innovation Road II
Science Park
Hsinchu 300
Ta i w a n
[email protected] [phone] ftp.zyxel.com
ftp.europe.zyxel.com
CZECH REPUBLIC
[email protected]om [phone] www.zyxel.cz ZyXEL Communications
Czech s.r.o.
Modranská 621
143 01 Praha 4 - Modrany
Ceská Republika
[email protected]om [phone]
DENMARK
[email protected] [phone] www.zyxel.dk ZyXEL Communications A/S
Columbusvej
2860 Soeborg
Denmark
[email protected] [phone]
FINLAND
[email protected] [phone] www.zyxel.fi ZyXEL Communications Oy
Malminkaari 10
00700 Helsinki
Finland
[email protected] [phone]
FRANCE
[email protected] [phone] www.zyxel.fr ZyXEL France
1 rue des Vergers
Bat. 1 / C
69760 Limonest
France
[phone]
GERMANY
[email protected] [phone] www.zyxel.de ZyXEL Deutschland GmbH.
Adenauerstr. 20/A2 D-52146
Wuerselen
Germany
[email protected] [phone]
HUNGARY
[email protected] [phone] www.zyxel.hu ZyXEL Hungary
48, Zoldlomb Str.
H-1025, Budapest
Hungary
[email protected] [phone]
KAZAKHSTAN
http://zyxel.kz/support [phone] www.zyxel.kz ZyXEL Kazakhstan
43, Dostyk ave.,Office 414
Dostyk Business Centre
050010, Almaty
Republic of Kazakhstan
[email protected] [phone]
NORTH AMERICA
[email protected] 1-800-255-4101
[phone]
www.us.zyxel.com ZyXEL Communications Inc.
1130 N. Miller St.
Anaheim
CA 92806-2001
U.S.A.
[email protected] [phone] ftp.us.zyxel.com
NORWAY
[email protected] [phone] www.zyxel.no ZyXEL Communications A/S
Nils Hansens vei 13
0667 Oslo
Norway
[email protected] [phone]

ZyWALL 5/35/70 Series User’s Guide
Customer Support 8
POLAND
[email protected] [phone] www.pl.zyxel.com ZyXEL Communications
ul.Emilli Plater 53
00-113 Warszawa
Poland
[phone]
RUSSIA
http://zyxel.ru/support [phone] www.zyxel.ru ZyXEL Russia
Ostrovityanova 37a Str.
Moscow, 117279
Russia
[email protected] [phone]
SPAIN
[email protected] [phone] www.zyxel.es ZyXEL Communications
Alejandro Villegas 33
1º, 28043 Madrid
Spain
[email protected] [phone]
SWEDEN
[email protected] [phone] www.zyxel.se ZyXEL Communications A/S
Sjöporten 4, 41764 Göteborg
Sweden
[email protected] [phone]
UKRAINE
[email protected] [phone] www.ua.zyxel.com ZyXEL Ukraine
13, Pimonenko Str.
Kiev, 04050
Ukraine
[email protected] [phone]
UNITED KINGDOM
[email protected] [phone]
08707 555779 (UK only)
www.zyxel.co.uk ZyXEL Communications UK
Ltd.,11 The Courtyard,
Eastern Road, Bracknell,
Berkshire, RG12 2XB,
United Kingdom (UK)
[email protected] [phone] ftp.zyxel.co.uk
a. “+” is the (prefix) number you enter to make an international telephone call.
METHOD
LOCATION
SUPPORT E-MAIL TELEPHONEAWEB SITE
REGULAR MAIL
SALES E-MAIL FAX FTP SITE

ZyWALL 5/35/70 Series User’s Guide
9 Customer Support

ZyWALL 5/35/70 Series User’s Guide
Table of Contents 10
Table of Contents
Copyright .................................................................................................................. 2
Federal Communications Commission (FCC) Interference Statement ............... 3
Safety Warnings ....................................................................................................... 5
ZyXEL Limited Warranty.......................................................................................... 6
Customer Support.................................................................................................... 7
Table of Contents ................................................................................................... 10
List of Figures ........................................................................................................ 28
List of Tables .......................................................................................................... 40
Preface .................................................................................................................... 48
Chapter 1
Getting to Know Your ZyWALL ............................................................................. 50
1.1 ZyWALL Internet Security Appliance Overview ..................................................50
1.2 ZyWALL Features ..............................................................................................50
1.2.1 Physical Features .....................................................................................51
1.2.2 Non-Physical Features .............................................................................52
1.3 Applications for the ZyWALL ..............................................................................58
1.3.1 Secure Broadband Internet Access via Cable or DSL Modem .................58
1.3.2 VPN Application ........................................................................................58
1.3.3 Front Panel LEDs .....................................................................................59
Chapter 2
Introducing the Web Configurator........................................................................ 62
2.1 Web Configurator Overview ...............................................................................62
2.2 Accessing the ZyWALL Web Configurator .........................................................62
2.3 Resetting the ZyWALL .......................................................................................63
2.3.1 Procedure To Use The Reset Button ........................................................64
2.3.2 Uploading a Configuration File Via Console Port .....................................64
2.4 Navigating the ZyWALL Web Configurator ........................................................64
2.4.3 Navigation Panel .......................................................................................70

ZyWALL 5/35/70 Series User’s Guide
11 Table of Contents
Chapter 3
Wizard Setup .......................................................................................................... 80
3.1 Wizard Setup Overview ......................................................................................80
3.2.1 ISP Parameters ........................................................................................80
3.2.1.1 Ethernet ...........................................................................................80
3.2.1.2 PPPoE Encapsulation .....................................................................82
3.2.1.3 PPTP Encapsulation .......................................................................83
Chapter 4
Registration .......................................................................................................... 100
4.1 myZyXEL.com overview ...................................................................................100
4.1.1 Subscription Services Available on the ZyWALL ....................................100
Chapter 5
LAN Screens......................................................................................................... 106
5.1 LAN Overview ..................................................................................................106
5.2 DHCP Setup .....................................................................................................106
5.2.1 IP Pool Setup ..........................................................................................106
5.3 LAN TCP/IP ......................................................................................................106
5.3.1 Factory LAN Defaults ..............................................................................106
5.3.2 IP Address and Subnet Mask .................................................................107
5.3.3 RIP Setup ...............................................................................................107
5.3.4 Multicast ..................................................................................................108
5.4 DNS Servers ....................................................................................................108
Chapter 6
Bridge Screens..................................................................................................... 118
6.1 Bridge Loop ......................................................................................................118
6.2 Spanning Tree Protocol (STP) .........................................................................118
6.2.1 Rapid STP .............................................................................................. 119
6.2.2 STP Terminology ....................................................................................119
6.2.3 How STP Works .....................................................................................119
6.2.4 STP Port States ......................................................................................120
Chapter 7
WAN Screens........................................................................................................ 126
7.1 WAN Overview .................................................................................................126
7.2 Multiple WAN ....................................................................................................126
7.3 Load Balancing Introduction .............................................................................127
7.4 Load Balancing Algorithms ..............................................................................127
7.4.1 Least Load First ......................................................................................127
7.4.1.1 Example 1 .....................................................................................128
7.4.1.2 Example 2 .....................................................................................128

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Table of Contents 12
7.4.2 Weighted Round Robin ...........................................................................129
7.4.3 Spillover ..................................................................................................129
7.5 TCP/IP Priority (Metric) ....................................................................................130
7.7 Configuring Load Balancing .............................................................................133
7.7.1 Least Load First ......................................................................................134
7.7.2 Weighted Round Robin ...........................................................................135
7.7.3 Spillover ..................................................................................................135
7.9 WAN IP Address Assignment ...........................................................................138
7.10 DNS Server Address Assignment ..................................................................138
7.11 WAN MAC Address ........................................................................................139
7.12.1 WAN Ethernet Encapsulation ...............................................................139
7.12.2 PPPoE Encapsulation ...........................................................................142
7.12.3 PPTP Encapsulation .............................................................................146
7.14 Configuring Traffic Redirect ............................................................................150
7.16.1 AT Command Strings ............................................................................155
7.16.2 DTR Signal ...........................................................................................155
7.16.3 Response Strings ..................................................................................155
7.17 Configuring Advanced Modem Setup ............................................................155
Chapter 8
DMZ Screens ........................................................................................................ 158
8.2 Configuring DMZ ..............................................................................................158
8.5 DMZ Public IP Address Example .....................................................................164
8.6 DMZ Private and Public IP Address Example ..................................................165
Chapter 9
Wireless LAN ........................................................................................................ 170
9.1 Wireless LAN Introduction ................................................................................170
9.1.1 Additional Installation Requirements for Using 802.1x ...........................170
9.6 Wireless Security .............................................................................................178
9.6.1 Encryption ...............................................................................................179
9.6.2 Authentication .........................................................................................179
9.6.3 Restricted Access ...................................................................................180
9.6.4 Hide ZyWALL Identity .............................................................................180
9.7 Security Parameters Summary ........................................................................180
9.8 WEP Encryption ...............................................................................................180
9.9 802.1x Overview ..............................................................................................181
9.9.1 Introduction to RADIUS ..........................................................................181
9.9.1.1 Types of RADIUS Messages .........................................................181
9.9.2 EAP Authentication Overview .................................................................182
9.10 Dynamic WEP Key Exchange ........................................................................182
9.11 Introduction to WPA ........................................................................................183
9.11.1 User Authentication ...............................................................................183

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13 Table of Contents
9.11.2 Encryption .............................................................................................183
9.12 WPA-PSK Application Example .....................................................................184
9.13 Introduction to RADIUS ..................................................................................185
9.14 WPA with RADIUS Application Example ........................................................185
9.15 Wireless Client WPA Supplicants ...................................................................186
9.16.1 Static WEP ............................................................................................188
9.16.2 WPA-PSK .............................................................................................189
9.16.3 WPA ......................................................................................................191
9.16.4 IEEE 802.1x + Dynamic WEP ..............................................................192
9.16.5 IEEE 802.1x + Static WEP ....................................................................193
9.16.6 IEEE 802.1x + No WEP ........................................................................194
9.16.7 No Access 802.1x + Static WEP ...........................................................195
9.16.8 No Access 802.1x + No WEP ...............................................................196
Chapter 10
Firewalls................................................................................................................ 198
10.1 Firewall Overview ...........................................................................................198
10.2 Types of Firewalls ..........................................................................................198
10.2.1 Packet Filtering Firewalls ......................................................................198
10.2.2 Application-level Firewalls ....................................................................198
10.2.3 Stateful Inspection Firewalls .................................................................199
10.3 Introduction to ZyXEL’s Firewall .....................................................................199
10.4 Denial of Service ............................................................................................200
10.4.1 Basics ...................................................................................................200
10.4.2 Types of DoS Attacks ...........................................................................201
10.4.2.1 ICMP Vulnerability ......................................................................203
10.4.2.2 Illegal Commands (NetBIOS and SMTP) ....................................203
10.4.2.3 Traceroute ...................................................................................204
10.5 Stateful Inspection ..........................................................................................204
10.5.1 Stateful Inspection Process ..................................................................205
10.5.2 Stateful Inspection and the ZyWALL .....................................................206
10.5.3 TCP Security .........................................................................................206
10.5.4 UDP/ICMP Security ..............................................................................207
10.5.5 Upper Layer Protocols ..........................................................................207
10.6 Guidelines For Enhancing Security With Your Firewall ..................................208
10.7 Packet Filtering Vs Firewall ............................................................................208
10.7.1 Packet Filtering: ....................................................................................208
10.7.1.1 When To Use Filtering .................................................................208
10.7.2 Firewall .................................................................................................209
10.7.2.1 When To Use The Firewall ..........................................................209

ZyWALL 5/35/70 Series User’s Guide
Table of Contents 14
Chapter 11
Firewall Screens................................................................................................... 210
11.1 Access Methods .............................................................................................210
11.2 Firewall Policies Overview ..............................................................................210
11.3 Rule Logic Overview ......................................................................................212
11.3.1 Rule Checklist .......................................................................................212
11.3.2 Security Ramifications ..........................................................................212
11.3.3 Key Fields For Configuring Rules .........................................................212
11.3.3.1 Action ...........................................................................................212
11.3.3.2 Service .........................................................................................213
11.3.3.3 Source Address ...........................................................................213
11.3.3.4 Destination Address ....................................................................213
11.4 Connection Direction Examples .....................................................................213
11.4.1 LAN To WAN Rules ...............................................................................213
11.4.2 WAN To LAN Rules ...............................................................................214
11.5 Alerts ..............................................................................................................214
11.10.1 Threshold Values ................................................................................223
11.10.2 Half-Open Sessions ............................................................................223
11.10.2.1 TCP Maximum Incomplete and Blocking Time ..........................224
11.11.2 Predefined Services ............................................................................229
11.12 Example Firewall Rule ..................................................................................231
Chapter 12
Intrusion Detection and Prevention (IDP) .......................................................... 236
12.1 Introduction to IDP .......................................................................................236
12.1.1 Firewalls and Intrusions ........................................................................236
12.1.2 IDS and IDP .........................................................................................237
12.1.3 Host IDP ..............................................................................................237
12.1.4 Network IDP .........................................................................................237
12.1.5 Example Intrusions ...............................................................................238
12.1.5.1 SQL Slammer Worm ...................................................................238
12.1.5.2 Blaster W32.Worm ......................................................................238
12.1.5.3 Nimda ..........................................................................................238
12.1.5.4 MyDoom ......................................................................................239
12.1.6 ZyWALL IDP .........................................................................................239
Chapter 13
Configuring IDP .................................................................................................... 240
13.1 Overview ........................................................................................................240
13.1.1 Interfaces ..............................................................................................240
13.2 General Setup ................................................................................................241
13.3.1 Attack Types .........................................................................................242
13.3.2 Intrusion Severity ..................................................................................244

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15 Table of Contents
13.3.3 Signature Actions ..................................................................................244
13.3.4 Configuring IDP Signatures ..................................................................245
13.3.5.1 Query Example 1 ........................................................................247
13.3.5.2 Query Example 2 ........................................................................249
13.4.1 mySecurity Zone ...................................................................................250
13.4.2 Configuring IDP Update ........................................................................251
Chapter 14
Anti-Virus .............................................................................................................. 254
14.1.1 Types of Computer Viruses .................................................................254
14.1.2 Computer Virus Infection and Prevention .............................................254
14.1.3 Types of Anti-Virus Scanner ................................................................255
14.2 Introduction to the ZyWALL Anti-Virus Scanner .............................................255
14.2.1 How the ZyWALL Anti-Virus Scanner Works .......................................256
14.2.2 Notes About the ZyWALL Anti-Virus .....................................................256
14.3 General Anti-Virus Setup ...............................................................................257
14.4.1 mySecurity Zone ...................................................................................259
14.4.2 Configuring Anti-virus Update ...............................................................259
Chapter 15
Anti-Spam ............................................................................................................. 262
15.1.1 Anti-Spam External Database ...............................................................262
15.1.1.1 SpamBulk Engine ........................................................................263
15.1.1.2 SpamRepute Engine ...................................................................263
15.1.1.3 SpamContent Engine ..................................................................263
15.1.1.4 SpamTricks Engine .....................................................................264
15.1.2 Spam Threshold ....................................................................................264
15.1.3 Phishing ................................................................................................264
15.1.4 Whitelist ................................................................................................265
15.1.5 Blacklist .................................................................................................265
15.1.6 SMTP and POP3 ..................................................................................265
15.1.7 MIME Headers ......................................................................................266
15.2 Anti-Spam General Screen ............................................................................266
Chapter 16
Content Filtering Screens ................................................................................... 274
16.1 Content Filtering Overview .............................................................................274
16.1.1 Restrict Web Features ..........................................................................274
16.1.2 Create a Filter List ................................................................................274
16.1.3 Customize Web Site Access ................................................................274
16.3 Content Filtering with an External Database ..................................................276
16.6 Customizing Keyword Blocking URL Checking ..............................................286
16.6.1 Domain Name or IP Address URL Checking ........................................286

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Table of Contents 16
16.6.2 Full Path URL Checking .......................................................................286
16.6.3 File Name URL Checking .....................................................................286
Chapter 17
Content Filtering Reports .................................................................................... 290
17.1 Checking Content Filtering Activation ............................................................290
17.2 Viewing Content Filtering Reports ..................................................................290
17.3 Web Site Submission .....................................................................................295
Chapter 18
Introduction to IPSec ........................................................................................... 298
18.1 VPN Overview ................................................................................................298
18.1.1 IPSec ....................................................................................................298
18.1.2 Security Association .............................................................................298
18.1.3 Other Terminology ................................................................................298
18.1.3.1 Encryption ...................................................................................298
18.1.3.2 Data Confidentiality .....................................................................299
18.1.3.3 Data Integrity ...............................................................................299
18.1.3.4 Data Origin Authentication ..........................................................299
18.1.4 VPN Applications ..................................................................................299
18.1.4.1 Linking Two or More Private Networks Together .........................299
18.1.4.2 Accessing Network Resources When NAT Is Enabled ...............299
18.1.4.3 Unsupported IP Applications .......................................................299
18.2 IPSec Architecture .........................................................................................300
18.2.1 IPSec Algorithms ..................................................................................300
18.2.2 Key Management ..................................................................................300
18.3 Encapsulation .................................................................................................300
18.3.1 Transport Mode ....................................................................................301
18.3.2 Tunnel Mode .........................................................................................301
18.4 IPSec and NAT ...............................................................................................301
Chapter 19
VPN Screens......................................................................................................... 304
19.1 VPN/IPSec Overview .....................................................................................304
19.2 IPSec Algorithms ............................................................................................304
19.2.1 AH (Authentication Header) Protocol ....................................................304
19.2.2 ESP (Encapsulating Security Payload) Protocol ..................................304
19.3 My ZyWALL ....................................................................................................305
19.4 Remote Gateway Address .............................................................................305
19.4.1 Dynamic Remote Gateway Address .....................................................306
19.5 Nailed Up .......................................................................................................306
19.6 NAT Traversal ................................................................................................306
19.6.1 NAT Traversal Configuration .................................................................307

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17 Table of Contents
19.7 ID Type and Content ......................................................................................307
19.7.1 ID Type and Content Examples ............................................................308
19.8 IKE Phases ....................................................................................................309
19.8.1 Negotiation Mode ..................................................................................310
19.8.2 Pre-Shared Key ....................................................................................310
19.8.3 Diffie-Hellman (DH) Key Groups ...........................................................311
19.8.4 Perfect Forward Secrecy (PFS) ...........................................................311
19.9 X-Auth (Extended Authentication) ..................................................................311
19.9.1 Authentication Server ...........................................................................311
19.15.1 Security Parameter Index (SPI) ..........................................................327
19.18 Telecommuter VPN/IPSec Examples ...........................................................333
19.18.1 Telecommuters Sharing One VPN Rule Example ..............................333
19.18.2 Telecommuters Using Unique VPN Rules Example ...........................334
19.19 VPN and Remote Management ...................................................................336
Chapter 20
Certificates............................................................................................................ 338
20.1 Certificates Overview .....................................................................................338
20.1.1 Advantages of Certificates ....................................................................339
20.2 Self-signed Certificates ..................................................................................339
20.3 Configuration Summary .................................................................................339
20.5.1 Certificate File Formats .........................................................................342
20.12 Verifying a Trusted Remote Host’s Certificate ..............................................357
20.12.1 Trusted Remote Host Certificate Fingerprints .....................................357
Chapter 21
Authentication Server.......................................................................................... 366
21.1 Authentication Server Overview .....................................................................366
21.1.1 Local User Database ............................................................................366
21.1.2 RADIUS ................................................................................................366
Chapter 22
Network Address Translation (NAT) ................................................................... 370
22.1 NAT Overview ................................................................................................370
22.1.1 NAT Definitions .....................................................................................370
22.1.2 What NAT Does ....................................................................................371
22.1.3 How NAT Works ...................................................................................371
22.1.4 NAT Application ....................................................................................372
22.1.5 Port Restricted Cone NAT ....................................................................373
22.1.6 NAT Mapping Types .............................................................................373
22.2 Using NAT ......................................................................................................374
22.2.1 SUA (Single User Account) Versus NAT ..............................................374
22.5 Port Forwarding ..............................................................................................379

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Table of Contents 18
22.5.1 Default Server IP Address ....................................................................380
22.5.2 Port Forwarding: Services and Port Numbers ......................................380
22.5.3 Configuring Servers Behind Port Forwarding (Example) ......................380
22.5.4 NAT and Multiple WAN .........................................................................381
22.5.5 Port Translation ....................................................................................381
Chapter 23
Static Route .......................................................................................................... 388
23.2 IP Static Route ...............................................................................................388
Chapter 24
Policy Route ......................................................................................................... 392
24.2 Benefits ..........................................................................................................392
24.3 Routing Policy ................................................................................................392
24.4 IP Routing Policy Setup .................................................................................393
Chapter 25
Bandwidth Management ...................................................................................... 398
25.2 Bandwidth Classes and Filters .......................................................................398
25.3 Proportional Bandwidth Allocation .................................................................399
25.4 Application-based Bandwidth Management ...................................................399
25.5 Subnet-based Bandwidth Management .........................................................399
25.6 Application and Subnet-based Bandwidth Management ...............................400
25.7 Scheduler .......................................................................................................400
25.7.1 Priority-based Scheduler ......................................................................400
25.7.2 Fairness-based Scheduler ....................................................................400
25.7.3 Maximize Bandwidth Usage .................................................................400
25.7.4 Reserving Bandwidth for Non-Bandwidth Class Traffic ........................401
25.7.5 Maximize Bandwidth Usage Example ..................................................401
25.7.5.1 Priority-based Allotment of Unused and Unbudgeted Bandwidth 402
25.7.5.2 Fairness-based Allotment of Unused and Unbudgeted Bandwidth ...
402
25.8 Bandwidth Borrowing .....................................................................................403
25.8.1 Bandwidth Borrowing Example .............................................................403
25.9 Maximize Bandwidth Usage With Bandwidth Borrowing ................................404
25.10 Configuring Summary ..................................................................................404
Chapter 26
DNS........................................................................................................................ 414
26.2 DNS Server Address Assignment ..................................................................414
26.3 DNS Servers ..................................................................................................414
26.4 Address Record .............................................................................................415
26.4.1 DNS Wildcard .......................................................................................415

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26.5 Name Server Record .....................................................................................415
26.5.1 Private DNS Server ..............................................................................415
26.6 System Screen ...............................................................................................416
26.8 Configure DNS Cache ....................................................................................421
26.10.1 DYNDNS Wildcard ..............................................................................424
26.10.2 High Availability ..................................................................................424
26.11 Configuring Dynamic DNS ...........................................................................424
Chapter 27
Remote Management ........................................................................................... 428
27.1 Remote Management Overview .....................................................................428
27.1.1 Remote Management Limitations .........................................................428
27.1.2 System Timeout ....................................................................................429
27.2 Introduction to HTTPS ....................................................................................429
27.4 HTTPS Example ............................................................................................432
27.4.1 Internet Explorer Warning Messages ...................................................432
27.4.2 Netscape Navigator Warning Messages ...............................................433
27.4.3 Avoiding the Browser Warning Messages ............................................434
27.4.4 Login Screen .........................................................................................434
27.6 How SSH works .............................................................................................437
27.7 SSH Implementation on the ZyWALL .............................................................438
27.7.1 Requirements for Using SSH ................................................................439
27.8 Configuring SSH ............................................................................................439
27.9 Secure Telnet Using SSH Examples ..............................................................440
27.9.1 Example 1: Microsoft Windows .............................................................440
27.9.2 Example 2: Linux ..................................................................................440
27.10 Secure FTP Using SSH Example ................................................................441
27.12 Configuring TELNET ....................................................................................442
27.14.1 Supported MIBs .................................................................................446
27.14.2 SNMP Traps .......................................................................................446
27.14.3 REMOTE MANAGEMENT: SNMP ......................................................446
27.17 Configuring CNM ..........................................................................................449
Chapter 28
UPnP...................................................................................................................... 452
28.1.1 How Do I Know If I'm Using UPnP? ......................................................452
28.1.2 NAT Traversal .......................................................................................452
28.1.3 Cautions with UPnP ..............................................................................452
28.1.4 UPnP and ZyXEL ..................................................................................453
28.2 Configuring UPnP ..........................................................................................453
28.4 Installing UPnP in Windows Example ............................................................455
28.4.1 Installing UPnP in Windows Me ............................................................456
28.4.2 Installing UPnP in Windows XP ............................................................457

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28.5 Using UPnP in Windows XP Example ...........................................................457
28.5.1 Auto-discover Your UPnP-enabled Network Device .............................458
28.5.2 Web Configurator Easy Access ............................................................459
Chapter 29
ALG Screen........................................................................................................... 462
29.1.1 ALG and NAT ........................................................................................462
29.1.2 ALG and the Firewall ............................................................................462
29.1.3 ALG and Multiple WAN .........................................................................462
29.2 FTP ................................................................................................................463
29.3 H.323 ..............................................................................................................463
29.4 RTP ................................................................................................................463
29.4.1 H.323 ALG Details ................................................................................463
29.5 SIP .................................................................................................................465
29.5.1 STUN ....................................................................................................465
29.5.2 SIP ALG Details ....................................................................................465
29.5.3 SIP Signaling Session Timeout ............................................................466
29.5.4 SIP Audio Session Timeout ..................................................................466
29.6 ALG Screen ....................................................................................................466
Chapter 30
Logs Screens........................................................................................................ 468
30.2 Log Description Example ...............................................................................469
30.2.1 Certificate Not Trusted Log Note ..........................................................470
30.4.1 Viewing Web Site Hits ...........................................................................476
30.4.2 Viewing Protocol/Port ...........................................................................476
30.4.3 Viewing Host IP Address ......................................................................478
30.4.4 Reports Specifications ..........................................................................479
Chapter 31
Maintenance ......................................................................................................... 480
31.1 Maintenance Overview ...................................................................................480
31.2 General Setup ................................................................................................480
31.2.1 General Setup and System Name ........................................................480
31.5 Pre-defined NTP Time Servers List ................................................................485
31.5.1 Resetting the Time ................................................................................485
31.5.2 Time Server Synchronization ................................................................485
31.6 Introduction To Transparent Bridging .............................................................487
31.7 Transparent Firewalls .....................................................................................487
31.11.1 Backup Configuration .........................................................................493
31.11.2 Restore Configuration ........................................................................493
31.11.3 Back to Factory Defaults ....................................................................495