To select the alternate feeds configure your client software to use the indicated port numbers. Currently down for a move and upgrade. I'm always looking to add new feeds. Issues People connecting from sites that have slow or broken DNS servers will experience startup delays, or in extremely rare cases the startup will fail completely. If the connection is not accepted, you may want to make sure that there is a valid hostname associated with your IP address.
Some corporate sites have firewalls between the internal network and the Internet.
The stated purpose is to keep evil hackers out. You should see the radio FREQ, RATE, DIST and SNR fields filled in. The port 2103 server is directly attached to a real survey-grade GPS reference station without an intervening radio. There isn't any radio involved that could send the data that this page is looking for. This page should and will stay blank.