15.1 Access Methods .............................................................................................................. 207
15.3 Rule Logic Overview ....................................................................................................... 208
15.3.1 Rule Checklist ........................................................................................................ 208
15.4 Connection Direction ....................................................................................................... 209
15.4.1 LAN to WAN Rules ................................................................................................. 210
15.4.2 Alerts ...................................................................................................................... 210
15.7 Example Firewall Rule ..................................................................................................... 217
15.8 DoS Thresholds .............................................................................................................. 221
15.8.1 Threshold Values ................................................................................................... 221
15.8.2 Half-Open Sessions ............................................................................................... 222
15.9 Firewall Commands ......................................................................................................... 224
Content Filtering ................................................................................................................... 227
Introduction to IPSec............................................................................................................ 231
17.1 VPN Overview ................................................................................................................. 231
17.1.1 IPSec ...................................................................................................................... 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
P-2602H(W)(L)-DxA User's Guide
...................................................................... 216
Table of Contents
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