This may be obvious stuff to many here, but it took me some time to work through so I thought I’d post it to save any newcomers some time.
The quick setup guide to the router works very well, so it’s somewhat tempting to just leave it like that, DON’T.
Firstly, all the firewall protections are off by default. It’s quite easy to enable these from the Services tab in the router setup.
I’m not a networking/security expert, but I know someone that is, they pointed me to the Shields Up! tests at www.grc.com. This quickly points out that the router has its HTTP, FTP and Telnet ports open by default and that especially an open Telnet port is bad news.
The main manual finally points out the problem (about chapter 21) and provides an alternative solution.
If F9 is listening, a note about security would not go amiss at the end of the quick setup guide. I called F9 support about security and was told to get a software firewall for all my PCs – this would not have solved the problem.
If anyone else has further or better advice, I’d appreciate it.