
ZyWALL 110/310/1100 Series User’s Guide
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ALG
15.1 ALG Overview
Application Layer Gateway (ALG) allows the following applications to operate properly through the
ZyWALL’s NAT.
• SIP - Session Initiation Protocol (SIP) - An application-layer protocol that can be used to create
voice and multimedia sessions over Internet.
• H.323 - A teleconferencing protocol suite that provides audio, data and video conferencing.
• FTP - File Transfer Protocol - an Internet file transfer service.
The following example shows SIP signaling (1) and audio (2) sessions between SIP clients A and B
and the SIP server.
Figure 135
SIP ALG Example
The ALG feature is only needed for traffic that goes through the ZyWALL’s NAT.
15.1.1 What You Can Do in this Chapter
Use the ALG screen (
) to set up SIP, H.323, and FTP ALG settings.
15.1.2 What You Need to Know
Application Layer Gateway (ALG), NAT and Firewall
The ZyWALL can function as an Application Layer Gateway (ALG) to allow certain NAT un-friendly
applications (such as SIP) to operate properly through the ZyWALL’s NAT and firewall. The ZyWALL
dynamically creates an implicit NAT session and firewall session for the application’s traffic from the
WAN to the LAN. The ALG on the ZyWALL supports all of the ZyWALL’s NAT mapping types.
Содержание ZyWALL 110 Series
Страница 16: ...ZyWALL 110 310 1100 Series User s Guide 16...
Страница 32: ...Chapter 1 Introduction ZyWALL 110 310 1100 Series User s Guide 32...
Страница 42: ...Chapter 3 Hardware Introduction ZyWALL 110 310 1100 Series User s Guide 42...
Страница 68: ...Chapter 4 Quick Setup Wizards ZyWALL 110 310 1100 Series User s Guide 68...
Страница 83: ...Chapter 6 Monitor ZyWALL 110 310 1100 Series User s Guide 83 Figure 60 Monitor System Status Interface Status...
Страница 128: ...Chapter 7 Interfaces ZyWALL 110 310 1100 Series User s Guide 128 Figure 83 Configuration Network Interface PPP Add...
Страница 135: ...Chapter 7 Interfaces ZyWALL 110 310 1100 Series User s Guide 135 Figure 85 Configuration Network Interface Cellular Add...
Страница 176: ...Chapter 7 Interfaces ZyWALL 110 310 1100 Series User s Guide 176...
Страница 186: ...Chapter 8 Trunk ZyWALL 110 310 1100 Series User s Guide 186...
Страница 210: ...Chapter 10 Routing Protocols ZyWALL 110 310 1100 Series User s Guide 210...
Страница 220: ...Chapter 12 DDNS ZyWALL 110 310 1100 Series User s Guide 220...
Страница 228: ...Chapter 13 NAT ZyWALL 110 310 1100 Series User s Guide 228...
Страница 240: ...Chapter 15 ALG ZyWALL 110 310 1100 Series User s Guide 240...
Страница 246: ...Chapter 16 IP MAC Binding ZyWALL 110 310 1100 Series User s Guide 246...
Страница 263: ...Chapter 18 Authentication Policy ZyWALL 110 310 1100 Series User s Guide 263...
Страница 264: ...Chapter 18 Authentication Policy ZyWALL 110 310 1100 Series User s Guide 264...
Страница 270: ...Chapter 19 Firewall ZyWALL 110 310 1100 Series User s Guide 270 Figure 163 Configuration Firewall...
Страница 296: ...Chapter 20 IPSec VPN ZyWALL 110 310 1100 Series User s Guide 296 Figure 182 Configuration VPN IPSec VPN VPN Gateway Edit...
Страница 316: ...Chapter 20 IPSec VPN ZyWALL 110 310 1100 Series User s Guide 316...
Страница 340: ...Chapter 22 SSL User Screens ZyWALL 110 310 1100 Series User s Guide 340...
Страница 442: ...Chapter 36 DHCPv6 ZyWALL 110 310 1100 Series User s Guide 442...
Страница 540: ...Appendix A Legal Information ZyWALL 110 310 1100 Series User s Guide 540...
Страница 558: ...Index ZyWALL 110 310 1100 Series User s Guide 558...
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