I moved into a building that provides free LAN internet access. They seem to be using 3BB as the ISP. I think I am connected directly to the modem/router, because accessing 192.168.1.1 gives me the router/ADSL modem login screen.

Here is my issue. Some ports do not work randomly. E.g. 8080 or 8000 (shoutcast radio streaming), or some other ports I use for SSH access (not default 22 port, I changed the port). But sometimes it works just fine. It seems the pattern is like this. I try to send an email thru SMTP server (port 587 - TLS), and it takes forever, even fails sometimes, but eventually goes thru. After an email or two all the ports get blocked. I have a feeling that ISP somehow monitors that port usage, and then blocks all port access except 80 to that account temporarily.

Has anyone else experienced that or anything similar with 3BB?

Thank you!

EDIT: 3GG -> 3BB

Yes i have, which is why i am dumping 3BB. No point having an 8mb connection if you can't download anything at reasonable speed.