Lexicon PCM92 manual Network Considerations and Limitations

(such as the Internet). Instead of using a dedicated, real-world connection such as a leased line, a VPN uses virtual connections through the public network. The advantage to a VPN is that your computer can be virtually connected to a local network even though it is physically anywhere in the world where you have an internet connection. This can also be done in a safe manner not compromising your local network’s security. If you would like to manage your PCM92 units remotely you should create a secure VPN con- nection.

There are many solutions on the market today that provide VPN access. These products offer different features, methods of VPN, complexity of setup and maintenance, as well as varying levels of security. It is beyond the scope of this manual to recommend a VPN solution that will best suit the needs of your network, although you will need a VPN that is capable of passing UDP and TCP traffic (most do). The PCM92 has been tested against several solutions and should work with all VPNs that meet these criteria. Please work with your system administrator and Internet ser- vice provider to find a VPN that will best fit your network. The 3Com OfficeConnect Secure Router (model # 3CR860-95) is one solution that has been tested, and is both inexpensive and simple to set up. It provides up to two concurrent VPN connections.

Network Considerations and Limitations

•Without a VPN, there can be no access from the outside world to any PCM92 that is behind a Network Address Translation (NAT) router. (One-to-One NAT and port forwarding will not work.)

•Firewall Considerations: The PCM92 uses port 3804 (udp and tcp) to communicate with the System Architect software. Make sure that you configure your firewalls correctly so that data sent to and from this port number can traverse your network.

Network Troubleshooting

If you are having difficulty getting your PCM92 to show up in your System Architect software, here are some things that you can try to resolve the prob- lem.

Software Firewall

If the PC that you have installed the System Architect software on has a built-in firewall you need to make sure that you allow the software the abili- ty to talk on your network. Try disabling your firewall and then going offline and back online in the System Architect software. If this fixes the problem, refer to your firewall manufacturer’s documentation on how to reconfigure your firewall to allow the System Architect software and/or port 3804 tcp and udp to pass through the firewall.

Ethernet Link

Make sure that you have a valid Ethernet connection by looking at the link status lights. Most Ethernet devices will have some kind of indicator that shows the link is present. Check the following connections:

•PCM92 device – If there is a valid connection on the PCM92 you will see a solid green LED.

•PC running the System Architect software

•Hub / Switch (if used)

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