Subject: [v4tov6transition] comments draft-tsou-v4v6tran-mobile-transition-guide

From: Cameron Byrne <[email-masked]>
Date: Mon, 20 Sep 2010 18:58:31 -0700

Few comments on this draft

1.  Gi-DS-lite is one of many paths for 3GPP IPv6, i do not think it
is relevant to focus only on this path.  I think it is more helpful to
say it is one of many paths. Architecturally, Gi-DS-Lite is not very
impactful in my mind. It is a relevant path. It is a dual-stack bearer
with a tunnel to an AFTR / CGN.  So, for me, it is just another
variant of DS + NAT44.  Sorry if my understanding of this is
simplistic.

2.  " Conversion of the private internal network to pure IPv6 operation
   should be an early objective, for at least two reasons. "

I do not think this is a prudent recommendation.  Various telco
systems are very specialized and barely do IPv4, if at all.  Many are
legacy TDM only interfaces.  Asking SigTran or Diameter or any of the
other telco systems to go IPv6 is hard, and will not achieve a lot
since they use so few addresses relative to the UE.  In my mobile
IPv6, we only have a use case / business case for transition the
mobile UE to IPv6 and the systems that interact directly with that
data bearer (top deck, mms, IMS ...).  There is no business case for
doing anything else with IPv6, especially internal systems.  If you
are just looking for experience with IPv6, setup test servers with
IPv6, not critical telco infrastructure.

3.   "As usual, because of the time it will take to transition all users,
   IPv4 access to the content and applications must continue to be
   provided, until the last Windows XP computer ceases to be tethered to
   a mobile device for Internet access."

It really bores me to read about XP.  The users today all have IPv4
addresses.  They work.  In my network, i have positioned the IPv6
offering as "new customers, new devices"  ... and no Legacy.  Growth
comes from new subscribers, not the legacy people on XP.  The good
thing about 3GPP mobile networks is that every UE when attaching to
the network today, it request IPv4 or IPv6.  If the service, the
customer, and the device are designed to be IPv6, then they can be
IPv6 without any legacy requirements on IPv4.

4.     3GPP specifications for mobile devices have required dual stack
   support for at least a year (i.e., as of Release 8.)

What does this mean?  How does it get enforced?   ... i don't think it
means anything and will not be enforced ....

5.   When the operator converts a given area to Gateway-Initiated DS-lite
   access, a number of public IPv4 addresses are freed because of the
   introduction of address sharing.

I think most large mobile operators already do address sharing, so
there is no gain here.

Regards,

Cameron