> On Wed, 31 Mar 2010, Dan Wing wrote: > > :: Users running IE6 today are IPv4-only users. If/when they go > :: to IPv6, they will be running Windows 7 and whatever browser > :: is shipped by Microsoft. > > Why do you say that? As far as I know, IE6 is an ipv6-capable > browser, > as long as it's going to FQDN's.. So, what about IE6/XP users who > installed bittorent clients (or spyware/trojans) that enabled > ipv6 for them without the user knowing about it?
Yes, thanks for correcting me. I agree they will have a poor experience (due to Teredo). But Remi's point is that those same systems (running Windows XP and IE6) using 6rd will be denied the ability to access content via IPv6. Which removes an incentive for ISPs to add 6rd (and offload the NAT44 they may soon have to install). > :: It seems solvably operationally, by asking ISPs to point their > :: IPv4-only subscribers at an ISP-operated DNS server which > :: purposefully breaks AAAA responses (returns empty answer), and > :: to point their dual-stack subscribers at an ISP-operated DNS > :: server which functions normally. > :: > :: Advanced IPv4-only users wanting to do AAAA queries (e.g., > :: Teredo users, 6to4 users, etc.) should be sufficiently advanced > :: to point themselves at the ISP's normal nameserver or a > :: public DNS server on the Internet (e.g., Hurricane > :: Electric's, Google's, etc.). That won't affect users running > :: uTorrent (which uses Teredo to provide IPv6 connectivity) > :: because it doesn't do AAAA queries to find peers. > > This is *exactly* what we are proposing -- the feature to > return empty > answers would be needed for ipv4-only subscribers in order to > keep them > ipv4-only. Also, if a fully ipv6-capable user visits that > person's home, > the recursor would then be able to make the call on if they > should pass > through AAAA to that particular user or not... I am by no > means advocating > to make this behavior a default, just a feature. I'm saying this should be do-able entirely within the ISP's DNS, without coordination or involvement with the content provider's DNS. For example, imagine the ISP's nameserver has a new "allow-aaaa-response" option that would be configured like: # # list IPv4 addresses that are known to have real IPv6 connectivity. # (e.g., this is all of the ISP's subscribers that are also # connected using 6rd). # acl aaaa_whitelist { 172.16.72.0/24; 192.168.1.0/24; }; ... options { ... allow-aaaa-response { aaaa_whitelist }; ... } Which should work until there is DNSSEC validation built into the subscriber's DNS client. I believe this is effectively what Nicholas described in http://www.ietf.org/mail-archive/web/dnsop/current/msg08339.html -d _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop