ZyXEL Communications 35 Series Network Router User Manual


 
ZyWALL 5/35/70 Series User’s Guide
Table of Contents 14
9.16.4 IEEE 802.1x + Dynamic WEP ..............................................................196
9.16.5 IEEE 802.1x + Static WEP ....................................................................197
9.16.6 IEEE 802.1x + No WEP ........................................................................198
9.16.7 No Access 802.1x + Static WEP ...........................................................199
9.16.8 No Access 802.1x + No WEP ...............................................................200
9.17 MAC Filter ......................................................................................................200
Chapter 10
Firewalls................................................................................................................ 202
10.1 Firewall Overview ...........................................................................................202
10.2 Types of Firewalls ..........................................................................................202
10.2.1 Packet Filtering Firewalls ......................................................................202
10.2.2 Application-level Firewalls ....................................................................202
10.2.3 Stateful Inspection Firewalls .................................................................203
10.3 Introduction to ZyXEL’s Firewall .....................................................................203
10.4 Denial of Service ............................................................................................204
10.4.1 Basics ...................................................................................................204
10.4.2 Types of DoS Attacks ...........................................................................205
10.4.2.1 ICMP Vulnerability ......................................................................207
10.4.2.2 Illegal Commands (NetBIOS and SMTP) ....................................207
10.4.2.3 Traceroute ...................................................................................208
10.5 Stateful Inspection ..........................................................................................208
10.5.1 Stateful Inspection Process ..................................................................209
10.5.2 Stateful Inspection and the ZyWALL .....................................................210
10.5.3 TCP Security .........................................................................................210
10.5.4 UDP/ICMP Security ..............................................................................211
10.5.5 Upper Layer Protocols ..........................................................................211
10.6 Guidelines For Enhancing Security With Your Firewall ..................................212
10.7 Packet Filtering Vs Firewall ............................................................................212
10.7.1 Packet Filtering: ....................................................................................212
10.7.1.1 When To Use Filtering .................................................................212
10.7.2 Firewall .................................................................................................213
10.7.2.1 When To Use The Firewall ..........................................................213
Chapter 11
Firewall Screens................................................................................................... 214
11.1 Access Methods .............................................................................................214
11.2 Firewall Policies Overview ..............................................................................214
11.3 Rule Logic Overview ......................................................................................216
11.3.1 Rule Checklist .......................................................................................216
11.3.2 Security Ramifications ..........................................................................216
11.3.3 Key Fields For Configuring Rules .........................................................216
11.3.3.1 Action ...........................................................................................216