If a user is sitting at a workstation running Dual Stack, and browses to a particular URL, does the workstation request a v6 or v4 address from DNS? Or is Windows code programed to request one or the other first? if so, does it request a v6 or v4 address first?
To the best of my knowledge, as long as a Windows client is not on an Active Directory domain network, it will prefer IPv6 addresses over IPv4. I believe that it sends out IPv6 and IPv4 requests, assuming an endpoint is available for both protocols. You can test this out by visiting a website that reports your publicly visible IP address such as http://myglobalip.com
Hope this helps!
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