I don't think the issue is so much with what ISP you're usng (internet access is internet access), but is your home network setup to allow remote access, which probably has more to do with your router/firewall settings, etc.....but someone more network savvy than me can confirm.
What/how are you trying to access at home? Remote Desktop? Vnc? FTP? Was it set up before now and did it work fine then?
Some things as mentioned require port forwarding, etc, and there are some issues recently with the Hitron modems and port forwarding.
Other modems those things seem to work fine.
Now, that is not to say that there could be something with the service there that is blocking it. They may only provide basic services out (http, pop/smtp, etc) but all other ports and types of connections are blocked, to prevent them being abused (torrents, etc)