T-Comfort 930 DSL, User Manual

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Configuration Examples Useful Information on Internet Access
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The IP addresses used in the LAN are translated into IP addresses valid worldwide. So you require no
such addresses for your LAN.
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Only IP connections triggered from a workstation can be established. Consequently, while you can call up
Web pages from a workstation, you cannot install a Web server visible in the Internet on a workstation.
Certain protocols cannot be used when NAT is being used. This affects protocols with the following prop-
erties:
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IP addresses are transported in the useful load, e.g. NetBIOS over TCP/IP.
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The protocol requires an active, inward-directed connection establishment, e.g. ICQ.
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The protocol will function without TCP/UDP port numbers, e.g. ICMP or IGMP.
The T-Comfort 930 DSL NAT has suitable processes for ensuring the functions of many important protocols
affected by these rules. These are the protocols FTP (in “active” mode), CuSeeMe (“videoconferencing”), IRC
(“chat”), ICMP errors (“traceroute”) and ICMP echo (“ping”).
Protocols which require inward-directed connection establishment can be configured in the Net Configu-
ration : Port Access menu. For further information, refer to the online help of this menu.