As a matter of fact Ron Broersma who affiliated with Space and Naval Warfare Systems Command (SPAWAR) has a list of equipment that should be fully IPv6-only com

As a matter of fact Ron Broersma who affiliated with Space and Naval Warfare Systems Command (SPAWAR) has a list of equipment that should be fully IPv6-only compliant including various management interfaces and more. The US Navy supposedly tests this in house in a IPv6-only network. 4 years later I imagine the situation only got better https://www.youtube.com/watch?v=9kQje5gSWw8 https://www.youtube.com/watch?v=9kQje5gSWw8 Also, AWS now have the majority of NICs and switches built in-house I imagine. The underlay network could be IPv6 or totally custom for what we know (but probably is IPv4).