Are IPv6-only Internet services viable today?

Thu Jan 14 23:20:32 UTC 2010

On Thu, Jan 14, 2010 at 3:00 PM, Jim Burwell <jimb at jsbc.cc> wrote:
> On 1/14/2010 11:10, Cameron Byrne wrote:
>> Folks,
>>
>> My question to the community is:  assuming a network based IPv6 to IP4
>> translator is in place (like NAT64 / DNS64), are IPv6-only Internet
>> services viable as a product today?  In particular, would it be
>> appropriate for a 3G /smartphone or wireless broadband focused on at
>> casual (web and email) Internet users?  Keep in mind, these users have
>> NAT44 today.
>>
> You may also want to read up on Dual Stack Lite (DS-Lite)
> <http://tools.ietf.org/html/draft-ietf-softwire-dual-stack-lite-02>,

I have looked at DS-lite very carefully.   First, DS-Lite fits better
for cable operators since they have CPE and can have a DS-lite
function in the CPE that they control, and that in turn allows them to
provide IPv4, IPv6, and dual-stack to the end-host that they do not
control.  DS-Lite does not fit as well for a mobile phones since it
would require a major change to the phone's OS.  Second, DS-Lite
requires tunneling as well as translation, so it is one more piece of
overhead in addition to NAT64 solution.  For me, i believe it is less
complex to manage a single stack IPv6 host with NAT64 translation than
a dual stack host, tunneling infrastructure, as well as NAT44 CGN,
which is what DS-lite requires.  They both achieve the same result,
but I believe in the mobile space there is a quicker time to market as
well as more progress toward the end-goal of IPv6-only using NAT64
than DS-lite.

> presuming you haven't.  I know you mentioned you didn't like any
> dual-stack solutions, but the thing about DS-Lite I like is that it has
> no problem with RFC1918 overlap of different customers, since the CGN
> uses a tunnel ID in the connection/NAT table in addition to the other
> typical data.  I just wonder how it will scale, since each device, or a
> gateway the device goes though, will require a IPv4-in-IPv6 tunnel to
> the CGN box(es).  Also, it doesn't require a DNS-ALG like NAT64/DNS64.

NAT64/DNS64 does not use a DNS-ALG.  DNS-ALG died with NAT-PT.  DNS64
is a standalone function which is decoupled from the translation
process.

>