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Industry Cellular Gateway
Virtual Server & NAT Loopback
"Virtual Server" allows you to access servers with the
global IP address or FQDN of the gateway as if they are
servers existed in the Internet. But in fact, these servers
are located in the Intranet and are physically behind the
gateway. The gateway serves the service requests by port
forwarding the requests to the LAN servers and transfers
the replies from LAN servers to the requester on the
WAN side. As shown in example, an E-mail virtual server
is defined to be located at a server with IP address
10.0.75.101 in the Intranet of Network-A, including SMTP
service port 25 and POP3 service port 110. So, the
remote user can access the E-mail server with the
gateway’s global IP 118.18.81.33 from its WAN side. But the real E-mail server is located at LAN side and the
gateway is the port forwarder for E-mail service.
NAT Loopback allows you to access the WAN global IP address from your inside NAT local network. It is useful
when you run a server inside your network. For example, if you set a mail server at LAN side, your local
devices can access this mail server through gateway’s global IP address when enable NAT loopback feature. On
either side are you in accessing the email server, at the LAN side or at the WAN side, you don’t need to change
the IP address of the mail server.
Virtual Computer
"Virtual Computer" allows you to assign LAN hosts to
global IP addresses, so that they can be visible to outside
world. While so, they are also protected by the gateway
firewall as being client hosts in the Intranet. For example,
if you set a FTP file server at LAN side with local IP
address 10.0.75.102 and global IP address 118.18.82.44,
a remote user can access the file server while it is hidden
behind the NAT gateway. That is because the gateway
takes care of all accessing to the IP address 118.18.82.44,
including to forward the access requests to the file
server and to send the replies from the server to outside
world
.
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