ZyXEL Communications P-2602H manual 17

		Table of Contents
15.1	Access Methods ..............................................................................................................	207
15.2	General Firewall Policy Overview ...................................................................................	207
15.3	Rule Logic Overview .......................................................................................................	208
15.3.1 Rule Checklist ........................................................................................................		208
15.3.2 Security Ramifications ............................................................................................		208
15.3.3 Key Fields For Configuring Rules ..........................................................................		209
15.4	Connection Direction .......................................................................................................	209
15.4.1 LAN to WAN Rules .................................................................................................		210
15.4.2 Alerts ......................................................................................................................		210
15.5	General Firewall Policy ...................................................................................................	210
15.6	Firewall Rules Summary ..................................................................................................	211
15.6.1 Configuring Firewall Rules ...................................................................................		213
15.6.2 Customized Services ............................................................................................		216
15.6.3 Configuring A Customized Service ......................................................................		216
15.7	Example Firewall Rule .....................................................................................................	217
15.8	DoS Thresholds ..............................................................................................................	221
15.8.1 Threshold Values ...................................................................................................		221
15.8.2 Half-Open Sessions ...............................................................................................		222
15.8.3 Configuring Firewall Thresholds .............................................................................		222
15.9	Firewall Commands .........................................................................................................	224
Chapter 16
Content Filtering ...................................................................................................................		227
16.1	Content Filtering Overview .............................................................................................	227
16.2	Configuring Keyword Blocking .......................................................................................	227
16.3	Configuring the Schedule ..............................................................................................	228
16.4	Configuring Trusted Computers .....................................................................................	229
Chapter 17
Introduction to IPSec............................................................................................................		231
17.1	VPN Overview .................................................................................................................	231
17.1.1 IPSec ......................................................................................................................		231
17.1.2 Security Association ...............................................................................................		231
17.1.3 Other Terminology ..................................................................................................		231
17.1.4 VPN Applications ...................................................................................................		232
17.2	IPSec Architecture ...........................................................................................................	232
17.2.1 IPSec Algorithms ....................................................................................................		233
17.2.2 Key Management ...................................................................................................		233
17.3	Encapsulation ..................................................................................................................	233
17.3.1 Transport Mode ......................................................................................................		234
17.3.2 Tunnel Mode .........................................................................................................		234
17.4	IPSec and NAT ................................................................................................................	234

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P-2602H(W)(L)-DxA User’s Guide