Draytek 200 User Manual

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VigorFly 200 Series User’s Guide 
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Local Area Network (LAN) is a group of subnets regulated and ruled by router. The design of 
network structure is related to what type of public IP addresses coming from your ISP. 
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The most generic function of Vigor router is NAT. It creates a private subnet of your own. As 
mentioned previously, the router will talk to other public hosts on the Internet by using public 
IP address and talking to local hosts by using its private IP address. What NAT does is to 
translate the packets from public IP address to private IP address to forward the right packets 
to the right host and vice versa. Besides, Vigor router has a built-in DHCP server that assigns 
private IP address to each local host. See the following diagram for a briefly understanding. 
 
In some special case, you may have a public IP subnet from your ISP such as 
220.135.240.0/24. This means that you can set up a public subnet or call second subnet that 
each host is equipped with a public IP address. As a part of the public subnet, the Vigor router 
will serve for IP routing to help hosts in the public subnet to communicate with other public 
hosts or servers outside. Therefore, the router should be set as the gateway for public hosts.