IPv6 /64 links (was Re: ipv6 book recommendations?)

Wed Jun 20 08:44:14 UTC 2012

valdis.kletnieks at vt.edu wrote:

>>     hosts.  However, for an ISP operating the NAT gateway, it may be
>>     easier to operate independent servers at default port for DNS, SMTP,
>>     HTTP and other applications for their customers than operating
>>     application relays.
> 
> So you're admitting that the NAT breaks things badly enough at the ISP
> level that running a forwarding ALG is easier than actually making the
> NAT work.

No, I don't. I just wrote that, if servers' port numbers are
not changeable, which has nothing to do with NAT, ISPs or
someone else can run servers, not ALGs.

It's like operating a server for whois, when whois commands
had a hard coded fixed IP address of the server. Note that,
at that time, the Internet was completely transparent that
your argument has nothing to do with the transparency.

>>> (HInt - we haven't solved that problem for NAT yet, it's one of the big
>>> reasons that NAT breaks stuff)
>>
>> As you can see, there is no such problem.
> 
> You haven't actually *deployed* your solution in a production environment,
> have you?

Because we still have enough IPv4 addresses, because most
users are happy with legacy NAT and because some people
loves legacy NAT, there is not much commercial motivation.

However, it does not invalidate end to end NAT as a counter
argument against people insisting on IPv6 so transparent with
a lot of legacy NAT used by people who loves it.

That is, end to end transparency can not be a reason to
insist on IPv6.

					Masataka Ohta