If a router still supports IPv4 is it IPv6 router?
Lately I've been thinking, isn't the true way to know whether a router is IpV6 that it no longer supports or passes any Ipv4 traffic? That seems like that it would be a pretty clear heuristic for telling whether it's a true Ipv6 router or not.
Since backwards compatibility is an important part of our discipline, I'm going to say no.
Nop, there a many layer 3 protocols beside the IP ones.