UAG4100 User’s Guide
199
C
H A P T E R
1 9
ALG
19.1 ALG Overview
Application Layer Gateway (ALG) allows the following application to operate properly through the
UAG’s NAT.
• FTP - File Transfer Protocol - an Internet file transfer service.
The ALG feature is only needed for traffic that goes through the UAG’s NAT.
19.1.1 What You Can Do in this Chapter
Use the
ALG
screen (
) to set up the FTP ALG settings.
19.1.2 What You Need to Know
Application Layer Gateway (ALG), NAT and Firewall
The UAG can function as an Application Layer Gateway (ALG) to allow certain NAT un-friendly
applications to operate properly through the UAG’s NAT and firewall. The UAG dynamically creates
an implicit NAT session and firewall session for the application’s traffic from the WAN to the LAN.
The ALG on the UAG supports all of the UAG’s NAT mapping types.
FTP ALG
The FTP ALG allows TCP packets with a specified port destination to pass through. If the FTP server
is located on the LAN, you must also configure NAT (port forwarding) and firewall rules if you want
to allow access to the server from the WAN.
ALG and Trunks
If you send your ALG-managed traffic through an interface trunk and all of the interfaces are set to
active, you can configure routing policies to specify which interface the ALG-managed traffic uses.
You could also have a trunk with one interface set to active and a second interface set to passive.
The UAG does not automatically change ALG-managed connections to the second (passive)
interface when the active interface’s connection goes down. When the active interface’s connection
fails, the client needs to re-initialize the connection through the second interface (that was set to
passive) in order to have the connection go through the second interface.
Содержание UAG4100
Страница 43: ...Chapter 3 Printer Deployment UAG4100 User s Guide 43 ...
Страница 118: ...Chapter 10 Interfaces UAG4100 User s Guide 118 Figure 76 Configuration Network Interface Ethernet Edit External Type ...
Страница 119: ...Chapter 10 Interfaces UAG4100 User s Guide 119 Figure 77 Configuration Network Interface Ethernet Edit Internal Type ...
Страница 129: ...Chapter 10 Interfaces UAG4100 User s Guide 129 Figure 82 Configuration Network Interface PPP Add ...
Страница 207: ...Chapter 20 UPnP UAG4100 User s Guide 207 Figure 133 Network Connections My Network Places Properties Example ...
Страница 221: ...Chapter 24 Web Authentication UAG4100 User s Guide 221 Figure 146 Configuration Web Authentication Web Portal ...
Страница 222: ...Chapter 24 Web Authentication UAG4100 User s Guide 222 Figure 147 Configuration Web Authentication User Agreement ...
Страница 267: ...Chapter 26 Billing UAG4100 User s Guide 267 Figure 184 Configuration Billing Payment Service Custom Service ...
Страница 355: ...Chapter 38 Certificates UAG4100 User s Guide 355 Figure 237 Configuration Object Certificate Trusted Certificates Edit ...
Страница 404: ...Chapter 41 Log and Report UAG4100 User s Guide 404 Figure 283 Configuration Log Report Email Daily Report ...
Страница 408: ...Chapter 41 Log and Report UAG4100 User s Guide 408 Figure 285 Configuration Log Report Log Settings Edit System Log ...
Страница 413: ...Chapter 41 Log and Report UAG4100 User s Guide 413 Figure 287 Configuration Log Report Log Settings Edit Remote Server ...
Страница 466: ...Appendix B Legal Information UAG4100 User s Guide 466 Environmental Product Declaration ...