In an IPv6 future, how will you solve IPv4 connectivity?

Cameron Byrne cb.list6 at
Mon Oct 11 20:00:30 CEST 2010

> I can make as many IPv4 addresses as I want using private
> IPv4.  Your statement assumes that a private IPv4 number is not usable.
> This is obviously wrong.

Thanks for correcting me.  Let me know how that goes for you.

>  The point of IPv6-only is that IPv4 is
>> exhausted.  Given that dual-stack has not seamlessly transitioned us
>> to IPv6 as it was envisioned 10 years ago, demand for IPv4 will soon
>> exceed supply. Hence, IPv6-only solutions.
> My point is an ISP that is "out" of public IPv4 must offer some IPv4
> solution.  That will be private IPv4.  I think this is a given.

Nope, not a given.  But, you can do that. Others will do something
else.  My advice is that you accurately count how much money you keep
plowing into IPv4.

> The only question is how to get that private IPv4 access to the
> public IPv4.  You can use a proxy, yes.  But NAT does everything a
> proxy will do plus a lot more.  Thus the proxy is redundant, it costs
> extra money for basically nothing.
>>> I also see little point in fielding a proxy that allows IPv4-only to
>>> surf the IPv6 Internet.  Fielding a proxy like this costs us money
>>> and it's a given that the major content providers will be dual stacked
>>> for many years yet.
>> My customers, cell phone consumers, are generally not interested in
>> IPv4 or IPv6 or Dual-stack.   They just want it to work.  If I do not
>> have the IPv4 addresses (public, private, bogon), the service will not
>> work.
> How would you not have sufficient IPv4 private?  Once you throw out the
> assumption that all cell phone hosts in your network must have direct
> IPv4 connectivity to all other hosts in your network, (which is what
> the use of private numbers essentially gives you) if you run out of
> 10.x.x.x numbers in a subnet, you just create another 10.x.x.x subnet and
> start over.

Been there, done that.  But, unfortunately it's not acceptable to not
have unique numbers since the future of mobile telephony is IMS SIP, i
presume you are in a different corner of the 'net.  In 4G, there is no
other solution for voice.  And yes, dual-stack costs more.  In some
cases, it literally costs 2x.  For example, existing 3GPP mobile
networks require unique attachments for IPv4 and IPv6, and i pay by
attachment to the equipment vendor.

Verizon Wireless has 40 instances of in their network
today.  Yes, they can go to 80 instances or 80,000 instances, but at
what point do we say IPv4 is "run out"? There is a lot of overhead and
hack that go into administering a very large scale network with
duplicate address space.

 In reality, very near the majority of my user's traffic goes to
Google and Facebook.  They both have IPv6 services today.   So, if i
deploy IPv6-only handsets today, for those handsets, very near the
majority of their ISP traffic will be IPv6 end to end native, no NAT
needed for Google and Facebook.  Today on IPv4, 100% NAT is needed.

So in summary:

1.  DS costs more for me, maybe not for you

2. There is A LOT of content on IPv6 today, and with just a few more
big players (Akamai and Yahoo are in the works), IPv4-only sites will
be the long tail.  IPv6 content means NAT64 is less expensive and more
reliable than NAT44 solutions.

3.  There will be IPv6-only hosts that will reach the internet via
NAT64, many people do it today and it works well.

>> I believe there are 2 separate problems one is in the access network
>> and one is in the content network.
>> If the access network is growing (anything mobile, devices in the home
>> like DVR ...), they need to move to IPv6 as soon as possible since
>> IPv4 is not growing.  It is a simple business continuity story.  If
>> the access network is not growing, the business case is less urgent,
>> but a good idea.
>> For content providers, they NEED to be dual stack to reach all their
>> possible eyeballs.  Once again, it is a simple business continuity
>> story.  Without dual-stack (from a service perspective), you will not
>> have the best method of reaching all your customers.
> Yes I agree those problems exist but I think there is too much emphasis
> on the notion that legacy IPv4-only hosts will want to access the IPv6
> Internet.  By the time that content providers out there are IPv6-only,
> Windows XP will be a distant memory, and most CPE devices that are IPv4-only
> will be close to 2 decades old  The legacy IPv4 hosts at that
> time will be in such a minority that the industry can cease catering to
> them.  They can run their own proxy servers if they want their 50-year-old
> VAX to access "the Internet"
> Ted
>> Cameron

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