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Re: *capable*: very true, but I think being capable is a useful indicator of an operator having at least thought of IPv6 and then actively taking steps to get it deployed.<br />Re: biases: yes, I suspect there may be biases like that, for instance Eastern vs. Western Europe. I was thinking of additional analysis that would weigh ASes based on the amount of IPv4 address space they have deployed. That might shed a little more light on biases.