Ping IPv4 addresses from an IPv6 host

Solution 1:

::ffff:0:74.125.226.80 is a dotted-decimal address, and not a real IPv6 address.

If you only have full, world-routable IPv6 address (with prefix and a /48) then you cannot communicate with the IPv4 world without a special tunnel.

They are for all intents and purposes two different protocols. You have two choices for communication between the two:

• Dual-stack. Have both IPv4 (behind a NAT if need be) AND IPv6 (with a world-routable IP, and a link-local address) installed and configured. OS's will try to use IPv6 first, and fall back to IPv4 if that fails. Just make sure you're configured correctly (not a dotted-decimal address like above) and it works pretty seamlessly.

• Tunnelling. If you have an IPv6 device, it needs to be aware of an IPv4 tunnel that it can use to broker your connections to the IPv4 world.