I know the ER605 is a NAT gateway for IPv4. This by default makes all the LAN devices behind the NAT unreachable from the Internet. If they do need access that is where port forwarding comes into play. This all breaks with the introduction of IPv6 routing on the ER605. IPv6 doesn't have NAT. As a result all the LAN devices are directly accessible from the Internet. WAN>LAN Firewall rules are needed to secure the LAN IPv6 networks. Also supporting IPv6 in the existing firewall functions would be a big help.