ZyXEL Communications NBG410W3G Series User Manual

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NBG410W3G Support Note

associated hosts. Client PCs need to configure IP address manually.

2. When choosing DHCP setting as a ‘Server’, the LAN will automatically assign IP, subnet,

gateway and DNS to the associated clients.

3. When choosing DHCP setting as a ‘Relay’, the LAN will forward the DHCP request to

another DHCP server.

Using NAT/Multi-NAT

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What is Multi-NAT?

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How NAT works

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NAT Mapping Types

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SUA versus Multi-NAT

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Example

Step 1. Applying NAT on WAN Interface

Step 2. Configuring NAT Address Mapping

Step 3. Using Multiple Global IP addresses for clients and servers (One-to-One, Many-to-One,

Server Set mapping types)

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Application -- Non NAT-Friendly Support

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What is Multi-NAT?

NAT (Network Address Translation-NAT RFC 1631) is the translation of an Internet Protocol address used

within one network to a different IP address known within another network. One network is designated the

inside

network and the other is the

outside

. Typically, a company maps its local inside network addresses to one

or more global outside IP addresses and "unmaps" the global IP addresses on incoming packets back into local

IP addresses. The IP addresses for the NAT can be either fixed or dynamically assigned by the ISP. In addition,

you can designate servers, e.g., a web server and a telnet server, on your local network and make them

accessible to the outside world. If you do not define any servers, NAT offers the additional benefit of firewall

protection. In such case, all incoming connections to your network will be filtered out by the NBG410W3G,

thus preventing intruders from probing your network.

The SUA feature that the NBG410W3G supports previously operates by mapping the private IP addresses to a

global IP address. It is only one subset of the NAT. The NBG410W3G supports the most of the features of the

NAT based on RFC 1631, and we call this feature as 'Multi-NAT'. For more information on IP address