Corporate networks with professional IT staff are where you'll find the legacy systems and equipment that get in the way of using IPv6. Home users have all been running operating systems with IPv6 on by default for years, and their routers are mostly new enough to make IPv6 work out of the box as soon as the ISP is ready.

Considering what's at stake if you accidentally make some part of your infrastructure routable it seems pretty reasonable corporate environments want to be very careful about IPV6 adoption. Personally I think they should still do it but if HSBC is in the news tomorrow after leaking customer details because of a routing woops there would be a lot of "they should have known better!" here and in the press. It's going to a take a long time for sensitive corporate environments to decide the rewards outweigh the risks.

I think any enterprise that fails in this way has way bigger issues, and I would expect to have already been compromised. Every single enterprise should already have the firewall rules on their edge routers that would prevent that set up even with IPv4 (remember, NAT is not intended as a security feature and only kind-of works like one. Any competent network engineer should not be relying on NAT to add any security).

Infrastructure that is "unroutable" is not usable. Whether you add a route from the outside world to your internal services is completely orthogonal to whether your protocol is IPv4 or IPv6.

my guess is that it's mobile phone traffic vs. laptops; I suspect a lot of mobile providers have been pushing ipv6 for their needs, as mobile device usage has been growing a lot faster than desktop usage in recent years.

Yes, seems likely. There is a similar spike in late December when less people are in offices due to Christmas holidays.

Yep. I've had IPv6 at home since I moved in mid-2012 and got comcast (my existing Airport Extreme supported it, and I got a DOCSIS modem on the supported-for-ipv6 list).

At work, only parts of our network do IPv6, 5 years later. Enterprise stuff is slow to change. :(

Netflix and YouTube have strong IPv6 support and chew through a lot of bandwidth, perhaps?

I came here to ask exactly the same question. I can only assume that entertainment activities (console gaming, video on demand, etc.) can bring the traffic to make such a difference.

If the high IPv6 is because people get it automatically because of Comcast, and other large providers - that would explain it.

It's interesting how the difference itself is increasing.