ZyXEL Communications Unified Security Gateway ZyWALL 300 User Manual page 18

Table of Contents
Chapter 18
ALG ........................................................................................................................................ 265
18.1 ALG Introduction .............................................................................................................. 265
18.1.1 Application Layer Gateway (ALG) and NAT ........................................................... 265
18.1.2 ALG and Trunks ..................................................................................................... 265
18.1.3 FTP ........................................................................................................................ 266
18.1.4 H.323 ...................................................................................................................... 266
18.1.5 RTP ........................................................................................................................ 266
18.1.6 SIP ......................................................................................................................... 267
18.2 Peer-to-Peer Calls and the ZyWALL ............................................................................... 268
18.2.1 VoIP Calls from the WAN with Multiple Outgoing Calls .......................................... 268
18.2.2 VoIP with Multiple WAN IP Addresses ................................................................... 268
18.3 ALG Screen ..................................................................................................................... 269
18.4 WAN to LAN SIP Peer-to-peer Calls Example ................................................................ 271
Part III: Firewall and VPN..................................................................... 275
Chapter 19
Firewall................................................................................................................................. 277
19.1 Firewall Overview ............................................................................................................ 277
19.2 Firewall Rules .................................................................................................................. 278
19.2.1 Rule Directions ....................................................................................................... 278
19.2.2 Firewall and VPN Traffic ......................................................................................... 280
19.3 Firewall Rule Example Applications ................................................................................ 280
19.4 Alerts ............................................................................................................................... 283
19.5 Asymmetrical Routes ....................................................................................................... 283
19.5.1 Virtual Interfaces and Asymmetrical Routes .......................................................... 283
19.6 Configuring the Firewall ................................................................................................... 284
19.6.1 Edit a Firewall Rule ................................................................................................ 286
19.7 Firewall Rule Configuration Example .............................................................................. 287
Chapter 20
IPSec VPN.............................................................................................................................. 291
20.1 IPSec VPN Overview ....................................................................................................... 291
20.1.1 IPSec SA Overview ................................................................................................ 292
20.1.2 Additional Topics for IPSec SA ............................................................................... 294
20.2 VPN Related Configuration ............................................................................................. 296
20.3 VPN Connection Screens ................................................................................................ 297
20.3.1 VPN Connection Summary .................................................................................... 297
20.3.2 VPN Connection Add/Edit IKE .............................................................................. 298
20.3.3 VPN Connection Add/Edit Manual Key .................................................................. 302
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ZyWALL USG 300 User's Guide