What I Did On World IPv6 Day

Mostly, I cursed Vodafone (my mobile Internet provider). First, they blackholed 6to4 traffic, so the default strategy used by Microsoft Windows Vista reliably timed out. Second, they suffered 100% packet loss on IPv4 packets through their network. Actually, they did appear to work on this. Traffic to and came back first, then traffic to www.google.com. At 1600Z (two-thirds of the way through World IPv6 Day) IPv4 service was restored. Third, they use 192.168/16 addresses for their network routers, which should have been a big clue about why IPv6 deployment should be a priority. Fourth, they drop ICMP, making ping and traceroute useless for customers. Fifth, they failed to communicate any of this to their customers. Their user forum is the closest thing they have to a dialogue with their customers, and there's nothing that says "we know about this, don't call". Sixth, they don't answer the phone when you call. I think they might be busy dealing with other unhappy users. That's 6 ways to fail at IPv6. Thanks, Vodafone. If you can't be a good example, you'll just have to serve as a horrible warning (as Catherine Aird said).

Failure recovery

I've been categorizing distributed system designs into four groups, according to how they recover from the loss of a single critical ele...