Chapter 21 ALG
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• There should be only one SIP server (total) on the ZyWALL’s private networks.
Any other SIP servers must be on the WAN. So for example you could have a
Back-to-Back User Agent such as the IPPBX x6004 or an asterisk PBX on the
DMZ or on the LAN but not on both.
• Using the SIP ALG allows you to use bandwidth management on SIP traffic.
• The SIP ALG handles SIP calls that go through NAT or that the ZyWALL routes.
You can also make other SIP calls that do not go through NAT or routing.
Examples would be calls between LAN IP addresses that are on the same
subnet.
• The SIP ALG supports peer-to-peer SIP calls. The firewall (by default) allows
peer to peer calls from the LAN zone to go to the WAN zone and blocks peer to
peer calls from the WAN zone to the LAN zone.
• The SIP ALG allows UDP packets with a specified port destination to pass
through.
• The ZyWALL allows SIP audio connections.
• You do not need to use TURN (Traversal Using Relay NAT) for VoIP devices
behind the ZyWALL when you enable the SIP ALG.
• Configuring the SIP ALG to use custom port numbers for SIP traffic also
configures the application patrol (see
) to use the same
port numbers for SIP traffic. Likewise, configuring the application patrol to use
custom port numbers for SIP traffic also configures SIP ALG to use the same
port numbers for SIP traffic.
Peer-to-Peer Calls and the ZyWALL
The ZyWALL ALG can allow peer-to-peer VoIP calls for both H.323 and SIP. You
must configure the firewall and NAT (port forwarding) to allow incoming (peer-to-
peer) calls from the WAN to a private IP address on the LAN (or DMZ).
VoIP Calls from the WAN with Multiple Outgoing Calls
When you configure the firewall and NAT (port forwarding) to allow calls from the
WAN to a specific IP address on the LAN, you can also use policy routing to have
H.323 (or SIP) calls from other LAN or DMZ IP addresses go out through a
different WAN IP address. The policy routing lets the ZyWALL correctly forward the
return traffic for the calls initiated from the LAN IP addresses.
For example, you configure the firewall and NAT to allow LAN IP address
A
to
receive calls from the Internet through WAN IP address
1
. You also use a policy
route to have LAN IP address
A
make calls out through WAN IP address
1
.
Configure another policy route to have H.323 (or SIP) calls from LAN IP addresses
B
and
C
go out through WAN IP address
2
. Even though only LAN IP address
A
Summary of Contents for ZyWALL USG 100 Series
Page 2: ......
Page 30: ...Table of Contents ZyWALL USG 100 200 Series User s Guide 30 ...
Page 31: ...31 PART I User s Guide ...
Page 32: ...32 ...
Page 46: ...Chapter 2 Features and Applications ZyWALL USG 100 200 Series User s Guide 46 ...
Page 64: ...Chapter 3 Web Configurator ZyWALL USG 100 200 Series User s Guide 64 ...
Page 186: ...Chapter 7 Tutorials ZyWALL USG 100 200 Series User s Guide 186 ...
Page 223: ...Chapter 8 L2TP VPN Example ZyWALL USG 100 200 Series User s Guide 223 ...
Page 224: ...Chapter 8 L2TP VPN Example ZyWALL USG 100 200 Series User s Guide 224 ...
Page 225: ...225 PART II Technical Reference ...
Page 226: ...226 ...
Page 240: ...Chapter 9 Dashboard ZyWALL USG 100 200 Series User s Guide 240 ...
Page 284: ...Chapter 10 Monitor ZyWALL USG 100 200 Series User s Guide 284 ...
Page 372: ...Chapter 13 Interfaces ZyWALL USG 100 200 Series User s Guide 372 ...
Page 382: ...Chapter 14 Trunks ZyWALL USG 100 200 Series User s Guide 382 ...
Page 398: ...Chapter 15 Policy and Static Routes ZyWALL USG 100 200 Series User s Guide 398 ...
Page 412: ...Chapter 16 Routing Protocols ZyWALL USG 100 200 Series User s Guide 412 ...
Page 432: ...Chapter 19 NAT ZyWALL USG 100 200 Series User s Guide 432 ...
Page 437: ...Chapter 20 HTTP Redirect ZyWALL USG 100 200 Series User s Guide 437 ...
Page 438: ...Chapter 20 HTTP Redirect ZyWALL USG 100 200 Series User s Guide 438 ...
Page 460: ...Chapter 23 Authentication Policy ZyWALL USG 100 200 Series User s Guide 460 ...
Page 478: ...Chapter 24 Firewall ZyWALL USG 100 200 Series User s Guide 478 ...
Page 519: ...Chapter 25 IPSec VPN ZyWALL USG 100 200 Series User s Guide 519 ...
Page 520: ...Chapter 25 IPSec VPN ZyWALL USG 100 200 Series User s Guide 520 ...
Page 534: ...Chapter 26 SSL VPN ZyWALL USG 100 200 Series User s Guide 534 ...
Page 544: ...Chapter 27 SSL User Screens ZyWALL USG 100 200 Series User s Guide 544 ...
Page 546: ...Chapter 28 SSL User Application Screens ZyWALL USG 100 200 Series User s Guide 546 ...
Page 554: ...Chapter 29 SSL User File Sharing ZyWALL USG 100 200 Series User s Guide 554 ...
Page 639: ...Chapter 34 IDP ZyWALL USG 100 200 Series User s Guide 639 ...
Page 640: ...Chapter 34 IDP ZyWALL USG 100 200 Series User s Guide 640 ...
Page 661: ...Chapter 35 ADP ZyWALL USG 100 200 Series User s Guide 661 ...
Page 662: ...Chapter 35 ADP ZyWALL USG 100 200 Series User s Guide 662 ...
Page 694: ...Chapter 37 Content Filter Reports ZyWALL USG 100 200 Series User s Guide 694 ...
Page 712: ...Chapter 38 Anti Spam ZyWALL USG 100 200 Series User s Guide 712 ...
Page 734: ...Chapter 39 Device HA ZyWALL USG 100 200 Series User s Guide 734 ...
Page 750: ...Chapter 40 User Group ZyWALL USG 100 200 Series User s Guide 750 ...
Page 756: ...Chapter 41 Addresses ZyWALL USG 100 200 Series User s Guide 756 ...
Page 768: ...Chapter 43 Schedules ZyWALL USG 100 200 Series User s Guide 768 ...
Page 784: ...Chapter 45 Authentication Method ZyWALL USG 100 200 Series User s Guide 784 ...
Page 806: ...Chapter 46 Certificates ZyWALL USG 100 200 Series User s Guide 806 ...
Page 818: ...Chapter 48 SSL Application ZyWALL USG 100 200 Series User s Guide 818 ...
Page 828: ...Chapter 49 Endpoint Security ZyWALL USG 100 200 Series User s Guide 828 ...
Page 880: ...Chapter 50 System ZyWALL USG 100 200 Series User s Guide 880 ...
Page 920: ...Chapter 54 Reboot ZyWALL USG 100 200 Series User s Guide 920 ...
Page 922: ...Chapter 55 Shutdown ZyWALL USG 100 200 Series User s Guide 922 ...
Page 942: ...Chapter 56 Troubleshooting ZyWALL USG 100 200 Series User s Guide 942 ...
Page 954: ...Chapter 57 Product Specifications ZyWALL USG 100 200 Series User s Guide 954 ...
Page 1126: ...Appendix F Open Software Announcements ZyWALL USG 100 200 Series User s Guide 1126 ...