T-Comfort Comfort Pro S, Mounting And Commissioning Manual

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Useful Information on Internet Access Configuration Examples
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Several workstations can share a single Internet access. You do not require a LAN access, only a single
account with the Internet service provider.
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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 computer 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
properties:
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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 Network : Port
Access menu. For further information, refer to the online help of this menu.