ZyXEL Communications Prestige 128 user manual Configuring for Internet Access

defined, all incoming inquiries will be filtered out by the Prestige even if you do have a server on your network. This can prevent intruders from probing your system.

The 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).

In summary:

1.SUA is an ideal, cost-effective solution for small offices with less than 20 hosts using a LAN to concurrently access the Internet or other remote TCP/IP network.

2.SUA can provide one server address to be accessed by Remote Dial-in Users, thus controlling the incoming packets.

3.SUA can provide firewall protection if you do not configure a server IP address. All incoming inquiries will be filtered out by the Prestige. Therefore, servers on your network are protected.

4.UDP and TCP datagrams can be routed. In addition, ICMP echo can also be routed.

The figure below shows an example of a small office connected to the Internet via a Single User Account using the Prestige. Note that if you enable the Single User Account feature, your local IP address MUST be selected from the list of IP addresses for private networks as defined by the IANA.

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