Re: teredo.ipv6.microsoft.com off?
On 17 jul 2013, at 23:09, Brian E Carpenter brian.e.carpen...@gmail.com wrote: On 17/07/2013 19:13, Ignatios Souvatzis wrote: ... Let me ask one thing... a couple of years ago, when I read the specification of Teredo, I was quite impressed by the details (If you accept the premise that you have to work around being jailed behind an IPv4 NAT) put into the protocol. One detail was that it is supposed to be lowest priority and so go automatically away (from the client end) as soon as some configued IPv6 is available on the link. Isn't that how it's implemented? Yes, but the result is that the host tries to use Teredo preferentially even if the IPv4 path is better; and if the Teredo path is broken the result is user pain (as with 6to4). I think the idea of deprecating Teredo is that now that native IPv6 is a serious option, the costs of Teredo outweigh the benefits,on average. (Unfortunately nobody ever wrote the Teredo equivalent of RFC6343.) Brian When connecting to IPv6 literals, it will use IPv6, yes. It wont resolve s for IPv6 connection using Teredo. This used to be the facts and big difference between Teredo and 6to4 and I would be surprised if that has changed. martin
Re: teredo.ipv6.microsoft.com off?
On 17/07/13 21:09, Brian E Carpenter wrote: On 17/07/2013 19:13, Ignatios Souvatzis wrote: ... Let me ask one thing... a couple of years ago, when I read the specification of Teredo, I was quite impressed by the details (If you accept the premise that you have to work around being jailed behind an IPv4 NAT) put into the protocol. One detail was that it is supposed to be lowest priority and so go automatically away (from the client end) as soon as some configued IPv6 is available on the link. Isn't that how it's implemented? Yes, but the result is that the host tries to use Teredo preferentially even if the IPv4 path is better; and if the Teredo path is broken That is the opposite of how it's supposed to work. Teredo addresses should be de-pref'd below everything else, and would thus only be used for connection to IPv6-only hosts if the host lacked other IPv6 connectivity. As someone else has pointed out, maybe it gets used for IPv6 literals, but not hostnames - the RFC 3484 table on windows ensures this.
Re: teredo.ipv6.microsoft.com off?
On 18 Jul 2013, at 11:29, Phil Mayers p.may...@imperial.ac.uk wrote: On 17/07/13 21:09, Brian E Carpenter wrote: On 17/07/2013 19:13, Ignatios Souvatzis wrote: ... Let me ask one thing... a couple of years ago, when I read the specification of Teredo, I was quite impressed by the details (If you accept the premise that you have to work around being jailed behind an IPv4 NAT) put into the protocol. One detail was that it is supposed to be lowest priority and so go automatically away (from the client end) as soon as some configued IPv6 is available on the link. Isn't that how it's implemented? Yes, but the result is that the host tries to use Teredo preferentially even if the IPv4 path is better; and if the Teredo path is broken That is the opposite of how it's supposed to work. Teredo addresses should be de-pref'd below everything else, and would thus only be used for connection to IPv6-only hosts if the host lacked other IPv6 connectivity. As someone else has pointed out, maybe it gets used for IPv6 literals, but not hostnames - the RFC 3484 table on windows ensures this. Indeed; that's how it *should* be. Tim
