ZyXEL Communications 641 manual Advantages of SUA, Single User Account Topology

Prestige 641 ADSL Internet Access Router

192.168.1.33

192.168.1.34

192.168.1.35

192.168.1.36

Same Network

Number

192.168.1.1

INTERNET

Prestige

The SUA network appears as a single host to the Internet.

Figure 3-5 Single User Account Topology

The IP address for the SUA 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 server, SUA offers the additional benefit of firewall protection. If no server is defined, all incoming inquiries will be filtered out by your Prestige, thus preventing intruders from probing your network. Your Prestige accomplishes this address sharing by translating the internal LAN IP addresses to a single address that is globally unique on the Internet. For more information on IP address translation, refer to RFC 1631, The IP Network Address Translator (NAT).

3.10.1 Advantages of SUA

In summary:

•SUA is a cost-effective solution for small offices to access the Internet or other remote TCP/IP networks.

•SUA supports servers to be accessible to the outside world.

•SUA can provide firewall protection if you do not specify a server. All incoming inquiries will be filtered out by your Prestige.

•UDP and TCP packets can be routed. In addition, partial ICMP, including echo and trace route, is supported.

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