Problems with removing NAT from a network
matthew at matthew.at
Thu Jan 6 11:18:41 CST 2011
On 1/5/2011 9:39 PM, Cameron Byrne wrote:
> I understand my users pretty well, they only go to a few web pages ...
> its the nature of the net. I assure you, i am not taking any undue
> risk with regards to web. Try our friendly user trial and give me
> your feedback, thats why i am running it.
I'm not particularly surprised that a mobile client platform has a
different access pattern than desktop users... not a whole lot of mobile
BitTorrent clients yet, for instance.
> Ah Skype. According to your web page you work at Skype. Skype is a
> well known IPv6 spoiler application. In fact, in the IETF and many
> other circles, Skype is the only app that we can't seem to get to work
> with IPv6. Are you here to help with that or to tell us that we need
> to keep IPv4 around indefinitely?
Indeed, I work at Skype now and Adobe (developing RTMFP) before that.
At this point (because not everyone has IPv6) this class of applications
(along with BitTorrent and ICE-using VoIP apps) needs to be able to use
your NAT64 to talk to peers that are IPv4-only. To do that, they need to
be able to discover your NAT64 even though they're not doing DNS lookups
to find the IPv4 addresses of peers.
This will take 1) a way to do this and 2) upgrades of the apps to take
advantage of it. It is impossible to do #2 until #1 is solved.
There's been discussion in BEHAVE about this topic...
draft-korhonen-behave-nat64-learn-analysis for instance. I even proposed
a solution that wasn't raised in that or previous documents here:
I suppose, since it hasn't been mentioned elsewhere, should be written
up as a draft if/when I have some free time)
> Skype should not be the IPv6 spoiler app when
> NEARLY EVERYTHING ELSE WORKS. Read the thread i mentioned, real
> users, real developers, real network that is IPv6-only. Notice that
> things generally work, those folks have hacked their way to perhaps
> even making Skype work.
There's lots of other apps that don't work. Skype is just the squeaky
wheel because it is so popular.
> Seriously, 95+% of my traffic is web and email, and STUN and ICE don't
> matter much to grandma as long as m.v6.facebook.com loads.
See my above comment about how I'm not surprised, given the specific
> As long as dual-stack is around, the app vendors don't have to move
> and network guys have to dream up hacks to support these legacy apps
> (CGN ....).
Dual-stack + NAT44 has a lot fewer unsolved corner cases *and* doesn't
require apps to be upgraded to do discovery of the NAT64 prefix(es)
(which, for some legacy apps that are no longer under development will
NAT64/DNS64 is an interesting experiment that works for >95% of the web.
But it isn't really a solution unless "the web" is all you care about.
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