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

From: Keith Moore <[email-masked]>
Date: Tue, 13 Nov 2001 09:30:17 -0500

[recipient list trimmed - this has nothing to do with smtp]

> As Dan writes, the IPv4 address space should be fully included in the
> IPv6 address space.

then please explain how it is possible for a host that only supports IPv4
to send a reply to a host that only has an IPv6 address - how is the v4
host sending a reply going to fit the v6 host's 128-bit address 
into the 32-bit destination address field of an IPv4 packet?

Keith

---

From: "Jeroen Massar" <[email-masked]>
Date: Tue, 13 Nov 2001 17:50:53 +0100

Keith Moore <[email-masked]> wrote:

> then please explain how it is possible for a host that only 
> supports IPv4 to send a reply to a host that only has an IPv6 address
- how 
> is the v4 host sending a reply going to fit the v6 host's 128-bit
address 
> into the 32-bit destination address field of an IPv4 packet?

See http://unfix.org/projects/ipv6/IPv6andIPv4.gif

IPv6 -> IPv4 = NAT-PT
IPv4 -> IPv6 = Socks5, with a IPv4->IPv6 conversion as the proxy will be
dual homed and gets the dnsname of the remote (IPv6) host through
SOCKS..

Or one could use some magic with 6tunnel or redir and many other
programs..

Lets asume IPv4-only host wants to connect to an IPv6 SMTP host.
The admin sets up the following on his dual-homed gateway:

# ipfw add fwd 127.0.0.1,7025 tcp from any to 10.250.0.25 25
# redir --lport=7025 --laddr=127.0.0.1 --cport=25
--caddr=remote.ipv6.enabled.mx.example.org

Et tada..... all the IPv4 hosts going through the gateway trying to
connect to 10.250.0.25 port 25 will be 'redirred' to
remote.ipv6.enabled.mx.example.org.

This ain't really nice... but one could setup at least 1 host which
takes care of IPv4-only to IPv6-only conversion.
And especially with mail-relay systems this could be quite nice...
Ofcourse one would be better off setting up a IPv6&IPv4 mailrelay on the
gateway.. but alas it's only an example ;)

Greets,
 Jeroen

PS: And yeps without those gates there will be no talk between the IPv6
and the IPv4 world but you already figured that one out...

---

From: Keith Moore <[email-masked]>
Date: Tue, 13 Nov 2001 12:37:23 -0500

> While I understand your argument shown below, I do not deny the need for
> translation; the private addresses in the IPv4 have to be translated
> anyway at the borders of the private/global address spaces of IPv4.  And
> I do not deny the need for ISPs to do so for the global address spaces.

Many kinds of translators have been defined.  None of them is a 
general-purpose solution; all of them fail to support some kinds of 
applications.  One of the major reasons for migrating to IPv6 is 
to enable applications that cannot work in the presence of 
address translation.

For this reason, it would not reasonable for an application running
on an IPv6 host to treat a "subsumed" IPv4 address as if it were the
address of an IPv6 host.  For similar reasons, it would not be reasonable 
for an ISP to impose DNS translators and NAT-PTs on its IPv6 customers 
that provided pseudo-IPv6 addresses for IPv4 hosts.  These things can be
useful in limited-purpose environments, but they need to be explictly
chosen by the customer rather than imposed by default.

Keith

---

From: Keith Moore <[email-masked]>
Date: Tue, 13 Nov 2001 12:49:49 -0500

right...clearly it's possible to set up many different kinds of tunnels
or translators, and these are quite useful when their limitations are
respected.  but that's not the same thing as providing a general-purpose 
IPv4<-->IPv6 translation service for everybody on the net, which is what 
I understood Dan to be proposing. 

Keith

---

From: "D. J. Bernstein" <[email-masked]>
Date: 13 Nov 2001 18:50:55 -0000

Keith Moore writes:
> a host that only supports IPv4

Irrelevant.

The question is whether hosts WITH IPV6 SOFTWARE also have to suffer the
administrative hassle of obtaining new addresses---non-IPv4-compatible
IPv6 addresses.

Upgrading software can be painful, but it's not as painful as upgrading
software _and_ maintaining two sets of addresses.

---Dan

---

From: "Jim Fleming" <[email-masked]>
Date: Tue, 13 Nov 2001 13:40:16 -0600

----- Original Message ----- 
From: "D. J. Bernstein" <[email-masked]>
> administrative hassle of obtaining new addresses---non-IPv4-compatible

Answer: YES...of course, some view that as an advantage.....

People will also have to pay for their domain names to be registered
in IPv6 servers....some companies also view that as an advantage...

They will not have to use the J-word :-)

Jim Fleming
http://www.ddj.com/articles/search/search.cgi?q=fleming
Oct93: The C+@ Programming Language

---

From: "Jeroen Massar" <[email-masked]>
Date: Tue, 13 Nov 2001 21:29:25 +0100

> administrative hassle of obtaining new addresses---non-IPv4-compatible
If you even did look at the picture, you might have noticed that the
::ffff:<ipv4> gateway is "yet another router"
so...... the only thing that needs to be done for an IPv6 host is get a
routable IPv6 IP.... and make sure it gets a route to a router which
handles the ::ffff:<ipv4> range...

> software _and_ maintaining two sets of addresses.
Welps.... that's not required... as it's "yet another route"...

I hope that finally makes it all clear...

Greets,
 Jeroen

---

From: Keith Moore <[email-masked]>
Date: Tue, 13 Nov 2001 16:43:10 -0500

> administrative hassle of obtaining new addresses---non-IPv4-compatible

for hosts that have v4 addresses and 6to4 support, there's no administrative 
hassle.  they can simply use 2002:[v4 addr]::1

Keith

---

From: "D. J. Bernstein" <[email-masked]>
Date: 13 Nov 2001 21:35:27 -0000

Jeroen Massar writes:
> the only thing that needs to be done for an IPv6 host is get a
> routable IPv6 IP

Why should I do this manually? Why doesn't the software _automatically_
give me an IPv4-compatible IPv6 address, as explained in RFC 2893?

Our system administrators are busy getting real work done. Do you expect
them to waste time figuring out how to join a useless network?

Some of our computers and routers already have IPv6 software. But we're
not going to bother configuring those machines to talk to the global
IPv6 network. If you want IPv6 addresses to be part of the Internet---if
you want them to be reachable from machines like ours---then you have to
give us software that does _not_ require extra configuration for IPv6.

---Dan

---

From: Tim Chown <[email-masked]>
Date: Wed, 14 Nov 2001 00:36:46 +0000 (GMT)

> give me an IPv4-compatible IPv6 address, as explained in RFC 2893?

If you do that, you're assuming that the host you want to communicate
with is also capable of handling automatic tunneling and thus has an
IPv4 compatible address.  If the target is IPv6 native (a valid IPv6
target) then RFC 2185 suggests a relay method for reaching the target
but a) you would need a local "default" IPv6 router capable of handling
automatic tunneling and b) you have the problem of how the packet gets
routed back if the source address is IPv4-compatible (which RFC 2893 
says it can be).  Compatible addresses can add complexity.  Anyway, 
you need a v6 router if you want to talk to all v6 hosts.

Also, if of course you don't have a globally routable IPv4 address, you 
can't use IPv4-compatible addressing for global tunneling.   So anyone
behind a NAT wouldn't have any use for (off-site) compatible addresses
(you must have a few NATs over in Tonga? ;-)

If you have an architecture with end-to-end tunnels only, how are you
protecting your IPv4 network if you're firewalling, and you now have
IP-in-IP potentially to any host inside your network?   Existing tunnel
brokers accept protocol 41 very trustingly.   What's the tunneling
overhead, in performance, bandwidth, state, etc, where all hosts may
initiate many tunneled connections?

What's the DNS implication?  A host indicates IPv4-compatible capability
by having an IPv4-compatible AAAA record, but it may also have native
or other connectivity (e.g. 6to4).  Adds complexity when you're also
selecting the protocol to use in a dual-stack node anyway.

There are tools for IPv4-IPv6 and IPv6-IPv4, and for connecting IPv6
islands via IPv4 (6to4), but there seems to be little advocation for 
flat end-to-end tunnelling.  To an even greater extent than tunnel brokers,
a world of IPv4-compatible IPv6 doesn't promote "genuine" deployment.  The
favoured direction seems to be 6to4.   ISATAP is a new contender for
intra-site auto tunneling, perhaps behind a 6to4 router.
 
The single hop end-to-end model certainly doesn't allow multicast, though
6to4 has problems there too.

> them to waste time figuring out how to join a useless network?

I would hope v4 admins would be tracking and experimenting with new
technology (as "new" as v6 is).  Making a deployment decision is up
to you, of course.  There's a wide range of transition tools (which I
suspect is part of the "no big picture" problem).
 
> give us software that does _not_ require extra configuration for IPv6.

There's a distinction between addresses and hosts.  Plug and play is
a supposed advantage of IPv6, but that assumes you're on link and seeing
an advertised prefix.  In potential consumer environments, that can be
hidden from the end user.

tim

---

From: "Jeroen Massar" <[email-masked]>
Date: Wed, 14 Nov 2001 01:50:41 +0100

> give me an IPv4-compatible IPv6 address, as explained in RFC 2893?
man rtadvd
man rtsold

Router Advertisements & Solicitations......
Which if your admins set the IPv6 routers up correctly will get you your
autoconfigged addresses...
And these tend to be globabaly routable (if set up correctly yadda yadda
yadda)

> them to waste time figuring out how to join a useless network?
Maybe they should READ, LEARN and UNDERSTAND before trying to do
something ???

> IPv6 network.
If you want to stay in your own cloud, ofcourse you can... your
decission... your problem...

> If you want IPv6 addresses to be part of the 
> Internet---if you want them to be reachable from machines like
ours---then 
> you have to give us software that does _not_ require extra
configuration for IPv6.

Are you completely clueless or something ????

---> Addresses need to be routable, either if they are IPv4 or IPv6
<----

And if that isn't the case ofcourse the other end isn't reachable....
well duhhh...

Greets,
 Jeroen

---

From: [email-masked]
Date: Wed, 14 Nov 2001 10:27:01 +0900

IMHO, this discussion is going nowhere.  everyone is commenting
	using different wording (the meaning of "including IPv4 address space"
	is totally different from one another).

itojun

---

From: Kenji Rikitake <[email-masked]>
Date: Wed, 14 Nov 2001 00:06:44 +0900

Keith:

While I understand your argument shown below, I do not deny the need for
translation; the private addresses in the IPv4 have to be translated
anyway at the borders of the private/global address spaces of IPv4.  And
I do not deny the need for ISPs to do so for the global address spaces.
If you claim I'm contradicting to myself, please describe the state of
the "full inclusion" which you define.

// Kenji

In the message <[email-masked]>
at Tue, Nov 13, 2001 at 09:29:55AM -0500,

---

From: "D. J. Bernstein" <[email-masked]>
Date: 14 Nov 2001 02:00:30 -0000

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.

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.

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. You have to slip IPv6 support into the
operating systems and applications and routers so that IPv6 works
_automatically_ over the existing IPv4 infrastructure. Then you have to
wait for everyone to upgrade.

---Dan

---

From: "D. J. Bernstein" <[email-masked]>
Date: 14 Nov 2001 02:31:41 -0000

Keith Moore writes:
> for hosts that have v4 addresses and 6to4 support, there's no
> administrative hassle.  they can simply use 2002:[v4 addr]::1

We ``can simply use'' an IPv4-compatible address too. However, no matter
how simple you think it is, we---and millions of other people---are not
going to do it if it means spending precious system administrator time.
Sorry, Keith, but that's how the world works.

---Dan

---

From: Erik Nordmark <[email-masked]>
Date: Wed, 14 Nov 2001 10:07:12 +0100 (CET)

> 	is totally different from one another).

Agreed.

How about the folks that want to change something in existing
specifications (RFCs) or I-Ds write an I-D complete with definitions of their
terminology, what problem they are solving, and the solution.

That way folks can participate more constructively in the discussion by
at least being on the same page.

  Erik

---

From: Jeroen Massar <[email-masked]>
Date: Wed, 14 Nov 2001 13:31:48 +0100 (CET)

> 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...

> _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...)

> 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

---

From: "Jim Fleming" <[email-masked]>
Date: Wed, 14 Nov 2001 06:54:35 -0600

----- Original Message ----- 
From: "Jeroen Massar" <[email-masked]>
> a IPv6 subnet from RIPE/APNIC/whatever for whatever reason.

Why will Linux users with their FREE O/S, pay for address space ?

Jim Fleming
http://www.IPv8.info
IPv16....One Better !!

---

From: "Jim Fleming" <[email-masked]>
Date: Wed, 14 Nov 2001 06:56:32 -0600

----- Original Message -----
> ::ffff::/96 and let that gateway do the NAT-PT or other conversion to the
IPv4 world.

There are much easier ways to do this, that also solve the IPv6 Privacy
Problem.

You might want to study "The IPv6 Privacy Problem".
http://www.google.com/search?q=IPV6+Privacy+Problem
IPv8 Addressing solves that problem

Jim Fleming
http://www.IPv8.info

---

From: Nathan Lutchansky <[email-masked]>
Date: Wed, 14 Nov 2001 09:56:21 -0500

> going to do it if it means spending precious system administrator time.

I'm not sure I understand why you're arguing, Dan.  There aren't very many 
people on this list who suggest that IPv6 MUST displace IPv4 as quickly as 
possible and at all costs.

Administrators will not use IPv6 if they have no reason to.  If there are
no benefits to supporting it, then nobody will bother with it.  That
sounds reasonable to me.  Nobody should be forced to use software they 
don't need.

What you're asserting, however, is that since no major applications
require IPv6 right now, IPv6 is doomed to failure.  Most of us hope this
short-sighted opinion proves incorrect.  There are many applications
available right now that would benefit substantially from IPv6 support,
but the developers have not been interested in incorporating it due to the
lack of IPv6 connectivity in an IPv4-only world.  If two separate users
would like to communicate using IPv6, there should be a mechanism to allow
them to do so.  That's the problem this working group is trying to tackle.

I am curious why you have added IPv6 support to your own software if
you're convinced that it will never be useful to the vast majority of your
users.  Surely there are other features you could have spent time on
instead of something "millions of people" will never need.  -Nathan

-- 
+-------------------+---------------------+------------------------+
| Nathan Lutchansky | [email-masked] |  Lithium Technologies  |
+------------------------------------------------------------------+
|  I dread success.  To have succeeded is to have finished one's   |
|  business on earth...  I like a state of continual becoming,     |
|  with a goal in front and not behind. - George Bernard Shaw      |
+------------------------------------------------------------------+

---

From: "Eugene M. Kim" <[email-masked]>
Date: Wed, 14 Nov 2001 11:25:09 -0800

> Sorry, Keith, but that's how the world works.

Sorry, please let me (and actually countless other) out of your
definition of `system administrator', as the definition is a bit too
narrow.  :-)

System administrators work primarily out of needs.  When there are some
new needs justified, they will implement it.  You're free to remain out
of 6to4 if you, as a sysadmin, don't see justifying reasons for 6to4.
However, please don't deny the fact that there *are* some sysadmins --
actually a lot -- that see the virtues of 6to4 not achievable with
IPv4-compatible addresses with reasonable ease.  (The natural ability to
have a whole /64 network behind a single fixed IPv4 address comes to
mind first.)

Regards,
Eugene

---

From: [email-masked]
Date: Wed, 14 Nov 2001 11:56:03 -0500

> everything useful is reachable through IPv4.

That's your right, of course.

Although there *is* one small flaw in the reasoning:

You *cant* reach the entire internet.  What you *can* reach is "the part
of the internet that you find useful at the current time".  This is very
different than "the entire Internet".

Mention the three letters 'N', 'A', and 'T' to Keith Moore ;)

> _continue_ to be reachable through IPv4. In short, IPv6 is a failure.

Nobody is going to do that *until there's a reason to bother*.

How quickly do you think IPv6 would deploy if Gartner released a
nice 8.5x11 color glossy report that said IPv6 was The Next Big
Thing for business applications, because it allowed enough address
space so the problems with getting 2 NAT'ed networks to talk to
each other can be resolved?

How quickly do you think IPv6 would deploy if msn.com or aol.com
provided <insert glitzy new product> as an IPv6 application?

How quickly do you think IPv6 would deploy if Quake4 supported it?

> wait for everyone to upgrade.

This is the same sort of wishful thinking that says "the only hope for
computer security is to make it work without any effort from the user".

Oddly enough, a lot of sites manage to get their users to do things
like install anti-virus software and personal firewall software, even
though it requires *some* effort.

Now that Microsoft has shipped IPv6 in Windows XP, most of the major
players now have IPv6 in their current product (only players I can
think of that aren't are Apple's OSX and SGI's Irix).  Now, we *do*
still have to wait for the upgrade crank to turn before "most" people
have been upgraded to IPv6 capable, so there's still a 3-5 year wait
before it becomes *really* common.

On the other hand, RFC882 came out in November 1983.  The HOSTS.TXT is
known to have been in use at least until August 1990, and may have been
updated throught 1992.

And even today, when you add a new system to the Internet, you often have
to tell it it's IP address, it's netmask, it's default router, and the
IP address of a nameserver.  Hardly "without any effort".

But somehow, the Internet and DNS have not been classified as failures
due to the incredible amount of work involved to get connected.  Users
grumble, but they do it - they've at least mostly gotten used to the
idea that they will occasionally have to put in some effort to keep their
machines functioning (be it upgrading, or patching, or fixing a corrupted
registry, or finding somebody willing to do it for them).

-- 
				Valdis Kletnieks
				Operating Systems Analyst
				Virginia Tech

---

From: "D. J. Bernstein" <[email-masked]>
Date: 15 Nov 2001 01:39:43 -0000

Nathan Lutchansky writes:
> you're convinced that it will never be useful to the vast majority of
> your users.

Wow. Where do you get these ideas?

I would like to see IPv6 succeed, simply because static addresses make
robust network applications easier to write. The fact that a modem burp
destroys a user's ssh login session, for example, can be traced directly
to the fact that IPv4 addresses are expensive.

If, however, the IPv6 transition plan remains at this idiotic ``people
climb mountains'' level of development, then IPv6 will not succeed in
the foreseeable future.

---Dan

---

From: "D. J. Bernstein" <[email-masked]>
Date: 15 Nov 2001 02:15:08 -0000

> provided <insert glitzy new product> as an IPv6 application?

Go ask Microsoft to move the MSN servers from IPv4 addresses to IPv6
addresses. Also ask them to switch all their public client addresses
from IPv4 to IPv6. See what they say.

An extension to the public Internet address space is a failure if the
extended addresses can't talk to the old addresses.

> computer security is to make it work without any effort from the user".

To a first approximation, the only hope for computer security is to make
it work without any effort from the user. In fact, the most successful
security products are _easier_ to use than the systems they replace.

The main exception is that attacks against low-security systems provide
some economic incentives to switch. NSA's Brian Snow commented at a
recent conference that web-site defacements are great advertising for
his team's computer-security work. (I resisted the urge to ask him
whether NSA has paid for any of this advertising.)

> IP address of a nameserver.  Hardly "without any effort".

This effort provides a huge reward: a connection to the Internet! Email,
the web, and so much more. (Despite this, people complain about the
effort, and so we have all sorts of automatic configuration systems.)

Now, what exactly is my reward for spending time setting up useless IPv6
addresses for my perfectly functional IPv4 machines?

---Dan

---

From: "D. J. Bernstein" <[email-masked]>
Date: 15 Nov 2001 02:33:58 -0000

Jeroen Massar writes:
> Example.com is new and only gets a IPv6 subnet from
> RIPE/APNIC/whatever for whatever reason.

At this point they're not connected to the Internet. Pretty damn stupid,
if they actually wanted Internet addresses.

>             MX 20 mail-ipv4.example.com.

Okay. With the help of an SMTP proxy having an Internet address, a web
proxy having an Internet address, etc., this company manages to connect
to the Internet. IPv6 is functionally identical to 10.* here.

Now, some people have noticed a little problem with this picture, which
is that there are only a few billion Internet addresses. How would you
suggest solving this problem?

---Dan

---

From: "Jeroen Massar" <[email-masked]>
Date: Thu, 15 Nov 2001 11:08:06 +0100

> if they actually wanted Internet addresses.
Nopes, not stupid it's just a case example, which completely answers
your question
and handles any if not all problems you forseen.

> to the Internet. IPv6 is functionally identical to 10.* here.
You mean RFC1918 addresses with the help of NAT?
If you want I can tell you how to NAT 'real' IPv4 space too, see the
previous message.

> suggest solving this problem?

I only need 1 IPv4 IP which can do HTTP/SMTP/NNTP/FTP/etc.
proxy/gatewaying/etc. to the IPv6 world.
Neeto huh? And yes this is yet-another-kind-of-NAT. But one time in the
future we won't have any
IPv4 addresses any more and everything will be IPv6, though when that
time comes is unforseeable at this moment.

The biggest point you are missing is the fact that there are 2
'internets' (the two clouds in my picture) which
though with some added help can communicate with each other.

If you can think up a great marvelous idea how to make sure IPv4 hosts
can reach any new extended address space be my guest.
It will be the same as telling a telephone made to handle 100 digits to
be able to handle 8000 digits -> you need to get a new telephone.

Case ('ipv4 admins only want to sit on their lazy asses') taken,
handled, no problems -> closed.

Greets,
 Jeroen

---

From: "D. J. Bernstein" <[email-masked]>
Date: 15 Nov 2001 07:41:32 -0000

Eugene M. Kim writes:
> The natural ability to have a whole /64 network behind a single fixed
> IPv4 address comes to mind first.

Which applications take advantage of this? What do they do?

How are those applications supposed to work in a future IPv6 world, for
people who _don't_ have IPv4 addresses?

---Dan

---

From: "Jim Fleming" <[email-masked]>
Date: Thu, 15 Nov 2001 08:53:34 -0600

----- Original Message ----- 
> though with some added help can communicate with each other.

It might help if you include the URL to the IETF's Architecture "picture".
> http://unfix.org/projects/ipv6/IPv6andIPv4.gif

Jim Fleming
http://www.IPv8.info
IPv16....One Better !!

---

From: Juan Fco Rodriguez Hervella <[email-masked]>
Date: Thu, 15 Nov 2001 16:25:19 +0100

> Sorry, Keith, but that's how the world works.

You are spending a lot of "precious system administrator time" writing
these e-mails.

I've spent less time making an IPv6 network than reading your mails.

--
******
JFRH
******

---

From: "Eugene M. Kim" <[email-masked]>
Date: Thu, 15 Nov 2001 11:58:20 -0800

> > The natural ability to have a whole /64 network behind a single fixed

(Glad you quoted this, because it must be noted that I made a mistake and
should've said /48 instead of /64.  Thank you. =))

> people who _don't_ have IPv4 addresses?

Your question is misleading.

It's not some specific *applications* that take direct advantages of
6to4, but certain *situations* that do.  There isn't (or shouldn't be)
any application that is specifically written to understand and work
within 6to4 environment, except for applications written to configure
and manage the 6to4 network itself.  If you can present valid classes
of IPv6 applications that must behave differently in 6to4 environment, I
will be happy to correct myself.

I am quite sure you already understand this, but let me give an example
situation FWIW.

Let's say: A dialup/DSL/cable subscriber gets only one IPv4 address for
her home, but has numerous computers at command.  Her ISP does not even
provide IPv6 access yet.  She wants to give each and every computer of
hers a globally-visible IPv6 address so she can use <insert some random
IPv6 application that uses peer-to-peer model here>. 1)

With 6to4 it is possible for her to set up a /48 globally-visible IPv6
network.  Applications within the /48 network doesn't have to know about
the fact that they are operating within 6to4 environment.  They just
behave like they should in non-6to4 networks and work fine.

Means: These applications will work in a future IPv6 world, for example
when she gets an IPv6 prefix in the 2001:: space and converts her 6to4
network to use this prefix, and also later when she gets rid of her good
and old IPv4 address.  Applications will still be able to reach the
global IPv6 Internet.  Whether they will be able to reach the global
IPv4 Network is beyond the scope of 6to4 and is being addressed
separately by other proposals.

Regards,
Eugene

1) If you're saying that `there is no such application right now so your
argument is pointless,' please think twice.  I am quite sure there will
be such applications in a near future, myself being a developer of one
(a chat system based on P2P model; this is my pet project).  IPv6 has
emerged largely because there are some limitations and needs to be
lifted and fulfilled better, but it does _not_ mean that IPv6 (or any
related technology such as 6to4) is meaningful only if there are some
applications that take advantage of it `right now.'  You would never
know if there's any application people are developing in the hope that
it will fit perfectly into the scenario made possible by 6to4.

---

From: "D. J. Bernstein" <[email-masked]>
Date: 16 Nov 2001 20:48:04 -0000

Jeroen Massar writes:
> proxy/gatewaying/etc. to the IPv6 world. Neeto huh?

Completely uninteresting. Every public server still has an IPv4 address,
so your network is functionally identical to a standard IPv4 NAT setup.

Meanwhile, despite heavy use of NAT, the available IPv4 address space
seems to be disappearing. How do you propose solving this problem?

> But one time in the future we won't have any IPv4 addresses any more
> and everything will be IPv6,

Aha! Now _that_ would be neat. If www.company.com can be safely deployed
on an IPv6 address, the problem described above will vanish! Wonderful.
There are other reasons that, as a programmer, I'd like to see this.

But how exactly do we get to that situation? The current situation is
that you'd have to be an idiot to rely on IPv6 for www.company.com. How
do we change this?

The underlying fact is that millions of Internet computers won't connect
to, and won't accept connections from, computers on IPv6 addresses. How
do we change this?

These fundamental aspects of the IPv6 transition have been horribly
mismanaged. Three examples:

   * Many network stacks and routers are providing ``IPv6 support,'' but
     this ``support'' doesn't do anything unless the sysadmin takes time
     to configure it.

     A small amount of extra effort would have provided an automatic
     IPv6-over-IPv4 tunnel using an IPv6 address computed globally from
     the IPv4 address.

   * A typical single-address server---for example, a small DNS server
     answering queries on 131.193.178.181---has to set up a second
     socket and pester the sysadmin for a second address if it's going
     to answer IPv6 queries.

     (Even if IPv6+IPv4 wildcards were supported by all IPv6 stacks,
     they would be unacceptable for these applications. Many machines
     have, for example, a DNS cache on one address, and a DNS server on
     another address. Same for SMTP servers.)

     A small amount of extra effort would have provided a unified
     IPv6/IPv4 socket that accepts connections on 131.193.178.181 _and_
     on the automatic IPv6 address described above, allowing these
     common servers to support IPv6 with a minimum of fuss.

   * We're now being told that IPv4 sysadmins ``SHOULD'' take the time
     to set up AAAA records for all their machines.

     A small amount of extra effort would have provided connectivity
     from IPv6 clients to existing A records, through the tunnels
     mentioned above.

In short, the transition cost is much larger than it needs to be. People
here seem to have lost sight of the problem that motivated IPv6 in the
first place.

---Dan

---

From: "Jeroen Massar" <[email-masked]>
Date: Sat, 17 Nov 2001 02:17:28 +0100

> so your network is functionally identical to a standard IPv4 NAT
setup.
You can't call a new phone which can handle 128 numbers long
phonenumbers with an 'old' phone supporting only 32 numbers now can you?
And calling an old phone from a new phone will require a gateway system
which handles the old phone and the new phone.
But I already said that a couple of times.

> seems to be disappearing. How do you propose solving this problem?
We don't. And if you look at the real numbers (free IPv4 space) there is
just enough IPv4 space left for the transition period between IPv4 and
IPv6.

> Aha! Now _that_ would be neat. If www.company.com can be 
> safely deployed on an IPv6 address, the problem described above will
vanish! 
> Wonderful. There are other reasons that, as a programmer, I'd like to
see this.
Please read Itojun's excellent "Implementing AF-independent application"
at http://www.kame.net/newsletter/19980604/ ) which reveals most
answers.
Maybe we will once see a 'native-tree' qmail supporting IPv6 or even
better AF independence, though it has ip_address struct ? :)

> to, and won't accept connections from, computers on IPv6 
> addresses. How do we change this?
> 
Well duh.... don't you have to configure a IPv4 router ?
But with IPv6 this is easier, just config your router to do rtsol's and
accept rtadv's from it's uplinks et tada it's configured.
Now you only have to give each downlink a portion of the IPv6 space it
gets from it's uplinks.

>      IPv6-over-IPv4 tunnel using an IPv6 address computed globally
from
That's where 6to4 is for (2002:<ipv4>::/48) (RFC 3056).
For microsoft's stack that can easily be done by setting up the 'client'
host:
 - Install the IPv6 stack (on XP this translates into: 'start->run "ipv6
install")
 - 6to4cfg -b
et tada your done and every other stack also has this kind of
ease-of-use.

>      socket and pester the sysadmin for a second address if it's going
An IPv6 aware application could simply listen on [::/0]:<port> and
accept all connections there.
All depends on how/where one writes it's program.
For the 'IPv6 address pestering part', if it's a DNS server it probably
falls under the authority of the admin,
which if that admin setup his network correctly and did it the easy way
the server would simply rtsol an IPv6 address.

>      another address. Same for SMTP servers.)
Would yet-another socket matter then ? ;)

>      common servers to support IPv6 with a minimum of fuss.
That currently depends on the stack.
Some stacks are mixed IPv4/IPv6 and some are IPv4&IPv6 in one.
Thus on some platforms/stacks a programmer needs to bind() only to IPv6
(and IPv4 comes in with the mapped way ::ffff::/96)
and on some to IPv6 and IPv4. (Yes, this is a not so very handy
situation but that's why there is that ./configure command ;)
 
>      to set up AAAA records for all their machines.
If you don't you simply won't have (easy) connectivity to the IPv6
world.
And today it's SHOULD, in a year or ten (or something ;) your boss says:
MUST.
Also if you don't want to do IPv6 then simply don't... but don't come
crawling back when you are to late with it.
Though as it really isn't that much work, except for some network
planning that shouldn't be a big problem.

>      from IPv6 clients to existing A records, through the tunnels
NAT-PT... (RFC 2766):
"route -A inet6 ::ffff::/96 <nat-pt-gw-IPv6-address>" on your IPv6 only
machine.
done...

> In short, the transition cost is much larger than it needs to be.
Which 'costs' ?
The biggest 'cost' is the hardware, which you most of the time already
have for IPv4.
'Simply' upgrade your existing routers to support IPv6 et tada...
Or setup an *BSD/Linux/Solaris/etc... box and let that create a tunnel
into the IPv6 internet and have 'native' IPv6 on the LAN/WAN...

> People here seem to have lost sight of the problem that motivated IPv6
in the first place.
You mean the size of the address space?
You mean the easy of management?
You mean the decrease of global routes?
etc...
Those are luckily all nicely covered and if something is not they should
be addressed ASAP (read: yesterday).

Also a nice new draft came up today on the ietf lists called
"Application Aspects of IPv6 Transition" see:
http://www.ietf.org/internet-drafts/draft-shin-ngtrans-application-trans
ition-00.txt

I think this is covering most of this discussion.

Greets,
 Jeroen

---

From: "Jim Fleming" <[email-masked]>
Date: Fri, 16 Nov 2001 19:45:04 -0600

----- Original Message -----
> I think this is covering most of this discussion.

http://www.siteofthesentient.com/beta.vhs.html
You will often hear people who wish to control this or that technology or choice complain about how Beta lost to VHS as proof that
people cannot be left free to choose what is best for themselves.
...
VHS was two hours long, Beta was only one hour.
...
Beta machines cost EIGHT HUNDRED DOLLARS more than VHS machines when the competition started.
...
The ivory tower "experts" thought that a video quality so small your TV couldn't duplicate it was more important than being able to
record a whole movie, and they wanted you to pay an extra $800.00 for it!

Jim Fleming
http://www.IPv8.info
IPv16....One Better !!

---

From: [email-masked]
Date: Thu, 15 Nov 2001 03:28:17 -0500

> effort, and so we have all sorts of automatic configuration systems.)

Yes, but the fact that lots of people do it *without* automatic configuration
shows that your point of "it won't happen unless there's zero cost" is not
true in the real world.  People *will* invest effort if needed.
 
> addresses for my perfectly functional IPv4 machines?

The same reward as why people set up perfectly useless IPv4 addresses when
they had perfectly functional NCP addresses.  They saw a benefit to doing so,
even if not everybody agreed.

The same reward as why people install mail software that does RFC1894 status
notifications.  They saw a benefit to doing so, even if not everybody agreed.

Given that we have historic proof that companies are *more* than willing
to say "If you don't have a Flash plugin, we don't care if you take your
business elsewhere", or "If you don't have IE, we dont care", it may be
a very bad idea to blindly assume that they will keep supporting IPv4
customers after they've moved their own network to IPv6 for whatever reason.

Yes, a company will lose customers if they go to IPv6.  On the other hand,
if a company can save $250K a year by going to IPv6 and cleaning up their
NAT jungle across 35 branch offices, and they lose $150K in sales to people
who are neither IPv6-ready nor able/willing to use a proxy/gateway, they're
still $100K ahead,

/Valdis

---

From: Paul Smith <[email-masked]>
Date: Sat, 17 Nov 2001 00:49:23 +0000

>seems to be disappearing. How do you propose solving this problem?

The obvious answer is to charge people for IP addresses rather than the 
current system of giving them away for free.

I'm convinced that lots of companies have loads more IP addresses than they 
really need. In the early days of the ARPANet/Internet, class A addresses 
were given to anyone who wanted them. I'm sure all those addresses aren't 
needed, but obviously the people who have them want to keep them since 
there's no reason for them not to,

Eg, I picked a number at random - 52.0.0.0/8. This is owned by 'dupont.com' 
who I'm sure are a wonderful company, but they 'only' have 85000 employees 
- why on earth do they need 16M IP addresses, even if each employee has 10 
PCs they've still got 15.9M spare addresses? They aren't an ISP so they 
aren't giving the addresses to other people.  There are other similar examples.

But if you start charging $10 per year per IP address, then anyone with a 
class A address who doesn't need it will give it back sharpish! (or even $1 
per year will still be $16M per year for a class A range..)

(Or maybe this is just me being naive...)

Paul				VPOP3 - Internet Email Server/Gateway
[email-masked]			http://www.pscs.co.uk/

---

From: "Jim Fleming" <[email-masked]>
Date: Mon, 19 Nov 2001 14:15:22 -0600

----- Original Message ----- 
From: <[email-masked]>

> even if not everybody agreed.

Sounds like the same reasoning why people add all of the TLDs to their name space.
Not everyone agrees, but some see a benefit. Why does the IETF oppose that ?

Of course, IPv6 is not on the Internet....so, it may not matter to IPv4 people
From: "Jeroen Massar" [email-masked]
"It's not on the IPv4 internet just like everything in the IPv6 world."

IPv8 users are connected via the IPv4 Internet.
More are connecting each day.

Jim Fleming
http://www.IPv8.info
IPv16....One Better !!

---

From: "Jim Fleming" <[email-masked]>
Date: Mon, 19 Nov 2001 14:17:45 -0600

----- Original Message ----- 
From: "Paul Smith" <[email-masked]>
> aren't giving the addresses to other people.  There are other similar examples.

It all boils down to fairness.
Which list do you think is more fair ?

The "toy" IPv4 Internet Early Experimentation Allocations ?
http://www.iana.org/assignments/ipv4-address-space
or
The Proof-of-Concept IPv8 Allocations ?
http://www.ntia.doc.gov/ntiahome/domainname/130dftmail/unir.txt

Why would people pay for Address Space, when it is FREE ?

Jim Fleming
http://www.DOT-BIZ.com
http://www.in-addr.info
3:219 INFO

---

From: "Jeroen Massar" <[email-masked]>
Date: Mon, 19 Nov 2001 22:52:22 +0100

> current system of giving them away for free.
No it's not..... it could be but it simply won't never happen in the
current state.

> there's no reason for them not to,
Read: Network renumbering (if you planned your network in the 80's to be
like this you sure ain't going to renumber it... :)
Answer: IPv6, which has many nice facilities for renumbering your
network without any hassle.

> per year will still be $16M per year for a class A range..)
Which simply will be taken from money generated by their income which
will let you and me and the rest of the world cough it up...

> (Or maybe this is just me being naive...)
Jups :)

Greets,
 Jeroen

CC's to smtp lists removed because they really won't give a <fill in
here>

---

From: Paul Smith <[email-masked]>
Date: Tue, 20 Nov 2001 09:36:16 +0000

>Why would people pay for Address Space, when it is FREE ?

But why should it be free? Any commodity which is in limited supply 
probably shouldn't be free, or people abuse the facility and grab that 
commodity in bulk while they can meaning that other people can't get it.

At something like $1 per IP address per year (retail - ISPs would get a 
discount..), it probably wouldn't really affect anyone who USES their IP 
addresses efficiently, but it would certainly make the hoarders rethink 
their situation.

If RIPE, APNIC, ARIN etc said 'in 12 months we will be charging people for 
IP addresses', people would HAVE TO pay for IP addresses or relinquish 
them. So, that's WHY people would pay for them..

The only problem I have with paying for IP addresses is - who would the 
money go to - but that's a separate issue.