Despite some detailed sleuthing, I could not get IPv6 working reliably on my WiFi/Ethernet local area network with its connection to our ISP, Comcast. The router would give up after a day or so, reporting ICMP6 checksum errors and shutting down IPv6 service. (IPv4 worked well, regardless.)
I had tried swapping out a lot of my devices, including routers, but nothing seemed to keep the service going for more than 24 hours. Lacking more elaborate packet inspection tools, I put the whole thing on the shelf.
Now, after 5 months of computer / Internet life, I thought I'd check in again. What do you know -- IPv6 is stable now. There have been quite a few updates to operating systems, routers, and other components since January, so it's not possible to say what made the difference. And Comcast may have secretly changed its service in a way that cured my bug. (The log still reports bursts of ICMP6 checksum errors, by the way.)
We may never know what happened, and that's a shame because it is good to know where the weak links are (or were) to help plan future developments.
Meanwhile, laissez les bon temps rouler! We are ready for the next century.
p.s. This is mainly a hobby activity. There is practically nothing you can do with IPv6 that you can't do with the common IPv4. (You can test your own IPv6 capability here.) Over time, since the IPv4 system is now almost out of available new addresses, new services will have to be provided on IPv6 only. But that may be a while yet.
