Proroute GEM420 4G M2M Router
GEM420 User Manual
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3.1.5.1 Configuration
1. NAT Loopback:
Allow you to access the WAN IP address from inside your local
network. This is useful when you run a server inside your network. For an
example, if you set a mail server at LAN side, your local devices can access this
mail server through gateway’s WAN IP address. You don’t need to change IP
address of mail server no matter you are at local side or go out. This is useful
when you run a server inside your network.
3.1.5.2 Virtual Server & Virtual Computer
3.1.5.2.1 Virtual Server
This gateway’s NAT firewall filters out unrecognized packets to protect your Intranet,
so all hosts behind this device are invisible to the outside world. If you wish, you can
make some of them accessible by enabling the Virtual Server Mapping. Press “Add”
button to add new rule for Virtual Server.
A virtual server is defined as a
Public Port
, and all requests to this port will be
redirected to the computer specified by the
Server IP.
Virtual Server can work with
Scheduling Rules
, and give user more flexibility on Access control. For the details,
please refer to
System->Scheduling
.
For example, if you have an
FTP server (Service port 21) at 192.168.123.1
, a
Web
server1 (Service port 80) at 192.168.123.2,
a
Web server2 (Service Port 8080 and
