802.11n
Wireless
ADSL
2/2+
Router
ADN
‐
4102
49
3.6.2.2 Virtual Server
Internet users would not be able to access a server on your LAN because of native NAT protection.The
“virtual server” feature solves these problems and allows internet users to connect to your servers.
The following table describes the parameters:
Field
Description
Service Type
You can select the common service type, for example,
AUTH
,
DNS
or
FTP
.
You can also define a service name.
If you select
Usual Service Name
, the corresponding parameter has the
default settings.
If you select
User-defined Service Name
, you need to enter the
corresponding parameters.
Protocol
Choose the transport layer protocol that the service type uses. You can
choose
TCP
or
UDP
.
WAN Setting
You can choose
Interface
or
IP Address
.
WAN Interface
Choose the WAN interface that will apply virtual server.
WAN Port
Choose the access port on the WAN.
LAN Open Port
Enter the port number of the specified service type.
LAN IP Address
Enter the IP address of the virtual server. It is in the same network segment
with LAN IP address of the router.
3.6.2.3 ALG
An application layer gateway (ALG) is a feature on ScreenOS gateways that enables the gateway to parse
application layer payloads and take decisions on them. ALGs are typically employed to support applications
that use the application layer payload to communicate the dynamic Transmission Control Protocol (TCP) or
