.I have set up a few routers before (netgear, xyzel etc) but the TPlink firewall options on the W9980 seem confusing to the novice and worryingly do not seem set as default ON as most would expect.
Like most home users I tend to avoid fiddling with the many options but hope to find the main options easy to set and confirm.
The manual is not that helpful on the issue of the firewalls and setting the rulesseems confusing - most home users just want the reassurance that a basic hardware firewall is ON.
There is an SPI firewall in addition to the more obvious IPV4+6 firewalls (that need rules defining).
The SPI firewall selection however is hidden under the WAN menu and after selecting the 'edit' hypertext link on the right, then clicking on the 'advanced' button lower on the page.

It is not clear that the firewall is OFF by default. The main side menus offer IPV4 and firewalls but these seem additional to the SPI firewall. It would be nice to have a clear link to the SPI firewall.

I'm not sure whether to select fullcone NAT or not on that page - any advice would be appreciated on setting the router to have a basic secure firewall operating.

The router replaced my BT homehub5 and connected well (forgot that it would not automatically reestablish my previous home network links and homegroup) so i've put the HH5 back for now until i get the hang of this one.