ZyXEL Communications P-2608HWL-Dx Series - Manual (Page 17)

P-2608HWL-Dx Series User’s Guide
Table of Contents 17
Chapter 16
Firewall Configuration ......................................................................................... 199
16.1 Access Methods .............................................................................................199
16.2 Firewall Policies Overview ............................................................................199
16.3 Rule Logic Overview .....................................................................................200
16.3.1 Rule Checklist .......................................................................................200
16.3.2 Security Ramifications ..........................................................................200
16.3.3 Key Fields For Configuring Rules .........................................................201
16.3.3.1 Action ..........................................................................................201
16.3.3.2 Service ........................................................................................201
16.3.3.3 Source Address ...........................................................................201
16.3.3.4 Destination Address ....................................................................201
16.4 Connection Direction ......................................................................................201
16.4.1 LAN to WAN Rules ...............................................................................202
16.4.2 Alerts .....................................................................................................202
16.5 General Firewall Policy ...............................................................................202
16.6 Firewall Rules Summary ...............................................................................203
16.6.1 Configuring Firewall Rules ...................................................................205
16.6.2 Customized Services ............................................................................208
16.6.3 Configuring A Customized Service ......................................................209
16.7 Example Firewall Rule ...................................................................................209
16.8 DoS Thresholds ............................................................................................213
16.8.1 Threshold Values ..................................................................................213
16.8.2 Half-Open Sessions ..............................................................................214
16.8.2.1 TCP Maximum Incomplete and Blocking Time ...........................214
16.8.3 Configuring Firewall Thresholds ............................................................215
Chapter 17
Content Filtering .................................................................................................. 217
17.1 Content Filtering Overview ............................................................................217
17.2 Configuring Keyword Blocking .....................................................................217
17.3 Configuring the Schedule .............................................................................218
17.4 Configuring Trusted Computers ...................................................................219
Chapter 18
IPSec VPN ............................................................................................................. 221
18.1 IPSec VPN Overview .....................................................................................221
18.1.1 IKE SA Overview ..................................................................................222
18.1.1.1 IP Addresses of the ZyXEL Device and Remote IPSec Router ..222
18.1.1.2 IKE SA Proposal .........................................................................223
18.1.1.3 Diffie-Hellman (DH) Key Exchange .............................................223
18.1.1.4 Authentication .............................................................................224
18.1.1.5 Extended Authentication .............................................................225