Multitech ProxyServer MTPSR1-202ST, User Manual, Page: 42 / 142

ProxyServer User Guide
42
MTPSR1-202ST
Enabling the Virtual Server
The virtual server feature of the ProxyServer allows you to have multiple servers on your local area
network (LAN) with one static IP address (from your ISP or Multi-Tech’s Global Dynamic WAN
Addressing) assigned to the WAN port. A normal internet connection requires a static IP address for
each server on your LAN. A normal Internet connection is shown in the following illustration.
Internet
Hub
Web Server
204.111.2.30
FTP Server
204.111.2.20
Router
Secure
LAN
Firewall
204.111.2.60
In a normal Internet connection with a router connected to the Internet, you need a static IP address
for each function (server) you want to perform on the Internet. For example, to have a Web server
browse the internet for you, you need an IP address so that the router knows where the traffic is
coming from and where to send the reply. In our normal Internet connection we have assigned an
address of 204.111.2.30 for the Web server, address 204.111.2.20 for the FTP server, and
204.111.2.60 for the Firewall.
To reduce the number of static IP addresses, the ProxyServer’s virtual enable feature allows you to
map multiple local servers to a single static IP address or to a Global Dynamic WAN port address.
The virtual server feature enables the ProxyServer to take requests from different servers (functions)
and interact with the Internet based on the functionality of the request. In the normal Internet
connection, this was a physical linkage to a specific IP address. The virtual server feature is a
functional connection. Functionality is defined by how the server is used; i.e., the Web server uses a
www-http protocol, an e-mail server uses pop-3 and SMTP protocol. Therefore, multiple requests
can be sent to the Internet over a single physical connection and the ProxyServer will know which
server is requesting service. The following illustration shows how a ProxyServer is connected to the
Internet with a single static IP address or Global Dynamic WAN port address and the same servers
used in the normal Internet connection are now connected to the Internet through the ProxyServer.
Now, if instead of mapping a static IP address from your ISP to the ProxyServer, you employed Multi-
Tech’s Global Dynamic WAN port addressing method, you no longer have to be concerned with a
single static IP address from your ISP. You can assign a predefined Global Dynamic WAN port
address to each of the ProxyServer’s WAN ports and then map your servers to that WAN port
address the same way you would map a static IP address from your ISP. The predefined Global
Dynamic WAN port addressing scheme is 0.0.0.1 for the WAN port.