ietf-smtp
[Top] [All Lists]

Re: (ngtrans) including ipv4 address space into ipv6 address space

2001-11-14 05:33:26



On 14 Nov 2001, D. J. Bernstein wrote:

Jeroen Massar writes:
your decission... your problem...

Speaking as an IPv4 administrator: _I_ don't have a problem. I have all
the addresses I need. I can reach the entire Internet, and the entire
Internet can reach me. I'm not going to waste my time setting up IPv6;
everything useful is reachable through IPv4.

Lets do it again.... going from your perspective...:
(Oh if you want I can tell it in Shrek style... maybe that reads easier...)

Let's say you currently have IPv4 space and that it can reach
anything in the IPv4 world... which is a good thing.
Along with the fact that in the IPv4 world nobody has to do anything to
reach the IPv6 world.... and yups I could understand that point of view...

Then company Example.com comes along.... Example.com is new and only gets
a IPv6 subnet from RIPE/APNIC/whatever for whatever reason.

Thus Example.com is only reachable over IPv6 and you are only reachable
over IPv4....

As Example.com wants you as a customer they also want you (and the rest
of the IPv4 world) to be able to connect to them.

Them connecting to you is easy, Example.com makes sure it gets a route to
::ffff::/96 and let that gateway do the NAT-PT or other conversion to the IPv4 
world.

So far so good... Example.com (IPv6) connecting to you (IPv4) works.

But as they also want the other way around they will need to do some
creative stuff.... for example take SMTP.... quite simple...:

Install a box somewhere with both IPv6 and IPv4 connectivity, install a
random MTA with support for IPv4 and IPv6 protocols which acts as a
relay...

example.com MX 10 mail-ipv6.example.com.
            MX 20 mail-ipv4.example.com.

mail-ipv6.example.com AAAA 3ffe:8114:2000:240::1
mail-ipv4.example.com A    10.100.13.42

Et tada..... example.com's SMTP is reachable by the IPv4 world.
(Which was wat itojun's draft was all about...)

HTTP is also something that's quite a requirement ofcourse... so the same
trick, install a proxy with IPv6 and IPv4 support and proxy it along to
the IPv6 box...


There are millions of other people in the same situation. So you would
have to be an idiot to make your company's public servers and clients
reachable only through IPv6. You would be cutting yourself off from the
Internet.

Nobody is going to do that. Consequently everything useful will
_continue_ to be reachable through IPv4. In short, IPv6 is a failure.
Remember IPX ??, OSI ??, slip ?? uucp ?? bitnet ?? hamradio ??
They all passed away some time or another and did it hurt? nopes...
Did it take some time? yups...
Did it use a gateway system? yups...

Quake over IPX...... Quake3 only does IPv4 TCP/IP... guess why the IPX is
out Quake 666 will nicely do IPv6 in time ;)

(Yeah yeah IPX is still in use and the others too, but you probably also
know of such translator/gateway service like KALI which allow you to put
those IPX bits over the TCP/IP line or even translate it to it...)

Perhaps _you_ have a problem with this situation. Perhaps you want IPv6
to succeed. Your only hope is to make IPv6 work WITHOUT ANY EFFORT FROM
THE IPV4 SYSTEM ADMINISTRATORS.
See above... the only 'effort' is the fact that they should be 'open' to
the situation...

You have to slip IPv6 support into the operating systems and applications
and routers so that IPv6 works _automatically_ over the existing IPv4 
infrastructure.
Ehmmmm AMS-IX (Amsterdam IX fyi) has native IPv6 support which nicely runs
along the IPv4 parts on the shared medium for some time now....
And there are some more IX'es also already doing this...

IPv6 has nothing to do with IPv4 except for the fact that their is a away
into IPv4 space with ::ffff::/96... and that it is a "we've learned from
the problems with IPv4" enhancement...

Then you have to wait for everyone to upgrade.
See the comment above... people will upgrade when interresting things come
along... and as most modern OS's support IPv6 there should be no problem
there... or didn't you (re)install the last say 10 years?

People upgrade all the time... upgrading to IPv6 isn't that big of a
deal... and if you don't do it today... good for you wait another day...
If the move to IPv6 is really catching on you'll have to do it anywayz.

Nobody is forcing someone IPv6 onto them.... it's currently still in the
"Chicken and Egg" fase... not many hosts, not many apps... but the IPv4
world was that also in the beginning.... actually in the beginning there
was only sendmail on the SMTP side... look at it now... it will grow...
But it all depends on developers and the network guys to figure it out if
they are going to use it... but there are many companies deploying it..
It might take some time... but it's probably inevitable that there one day
will be only an IPv6 world...

Greets,
 Jeroen


<Prev in Thread] Current Thread [Next in Thread>