T-Home Comfort Pro S, Installation Manual

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Useful Information on Internet Access Configuration Examples
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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 IP or SIP.
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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 Comfort Pro S 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”).
Depending on the internet telephony protocol (VoIP, SIP) the required NAT extension (“Full Cone NAT”) or
RTP-Proxy is activated on the Media Gateway Card.
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.