I run a small weather station that acts as a web server.  Recently it's become impossible to access it via the web, though I can still access it over my local network.  Some details:

• My ISP is AT&T using their Uverse service.
• The server was accessible from the web a month or so ago.
• The server has web address oaklandweather.no-ip.org, which currently resolves to 99.121.57.131, and probably will for some time.
• I can ping the server either over the LAN or via the web without trouble.
• An attempt to connect to the weather station as a web server (HTTP) times out.

I'm pretty sure that the Uverse gateway is set up correctly: It worked properly in the past and I haven't made any changes to it.  An inspection of the settings doesn't show anything obviously wrong.

Has AT&T changed its terms of service?  I vaguely remember the terms of service don't allow customers to run servers; but I can't find any such restriction in documents available on the web.  Also the (AT&T supplied) gateway has a function to explicitly open a "pinhole" allowing HTTP service from a computer on the customer side of the gateway.

Thanks - jon