P-202H Plus v2 User’s Guide
Table of Contents
10
6.6 Configuring Address Mapping
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71
6.6.1 Address Mapping Rule Edit
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72
Chapter 7
Dynamic DNS
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74
7.1 Dynamic DNS Overview
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74
7.1.1 DYNDNS Wildcard
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74
7.2 Configuring Dynamic DNS
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74
Chapter 8
Firewalls
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76
8.1 Firewall Overview
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76
8.2 Types of Firewalls
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76
8.2.1 Packet Filtering Firewalls
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76
8.2.2 Application-level Firewalls
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76
8.2.3
Stateful Inspection Firewalls
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77
8.3 Introduction to ZyXEL’s Firewall
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77
8.3.1 Denial of Service Attacks
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78
8.4 Denial of Service
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78
8.4.1 Basics
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78
8.4.2 Types of DoS Attacks
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79
8.4.2.1 ICMP Vulnerability
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81
8.4.2.2 Illegal Commands (NetBIOS and SMTP)
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81
8.4.2.3 Traceroute
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82
8.5 Stateful Inspection
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82
8.5.1 Stateful Inspection Process
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83
8.5.2 Stateful Inspection and the ZyXEL Device
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83
8.5.3 TCP Security
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84
8.5.4 UDP/ICMP Security
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84
8.5.5 Upper Layer Protocols
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85
8.6 Guidelines for Enhancing Security with Your Firewall
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85
8.6.1 Security In General
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85
8.7 Packet Filtering Vs Firewall
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86
8.7.1 Packet Filtering:
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86
8.7.1.1 When To Use Filtering
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87
8.7.2 Firewall
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87
8.7.2.1 When To Use The Firewall
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87
Chapter 9
Firewall Configuration
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88
9.1 Enabling the Firewall
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88
9.2 E-Mail
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88
9.3 Attack Alert
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90