Dave Crocker review of IPv6 case study in draft-iab-protocol-transitions-05

[dthaler@…]

Indeed, not until a few years after IPv4 runout in various Regional
Address Registry (RIR) regions did IPv6 deployment significantly
increase. The RIRs and others conducted surveys of different
industries and industry segments to learn why people did not deploy
IPv6 [IPv6Survey2011] [IPv6Survey2015], which commonly listed lack of
a business case, lack of training, and lack of vendor support as
primary hurdles. Arguably forward-looking companies collaborated
with ISOC on World IPv6 Day and World IPv6 Launch to jump start
global IPv6 deployment, and arguably their work gave vendors

What incentives did it give them?

incentives to support IPv6 well. Key aspects of World IPv6 Day and
World IPv6 Launch that contributed to their successes were the
communication mechanism, and the measurement metrics and contingency
plans that were announced in advance.

As a case study it will help to describe what constituted success for
these events and why those criteria were the right ones.

Several efforts have been made to mitigate the lack of a business
case. Some governments (South Korea, Japan) provided tax incentives
to include IPv6. Other governments (Belgium, Singapore) mandated
IPv6 support by private companies. Few of these had enough value to
drive significant IPv6 deployment.

The concern about lack of training is often a common issue in
transitions. Because IPv4 is so ubiquitous, its use is routine and
simplified with common tools, and it is taught in network training
everywhere. While IPv6 deployment was low, ignorance of it was no
obstacle to being hired as a network administrator or developer.

Organizations with the greatest incentives to deploy IPv6 are those
which continue to grow quickly, even after IPv4 free pool exhaustion.

Thaler Expires July 8, 2017 [Page 15]

Internet-Draft Planning for Transition January 2017

Thus, ISPs have had varying levels of commitment, based on the growth
of their user base, services being added (especially video over IP),

Really? That makes theoretical sense, but what is the data to support it?

and the number of IPv4 addresses they had available. Cloud-based
providers, including CDN and hosting companies, have been major
buyers of IPv4 addresses, and several have been strong deployers and
advocates of IPv6.

As an example, this fact mostly serves to highlight how difficult it is
to figure who has what incentive.

Different organizations will use different transition models for
their networks, based on their needs. Some are electing to use
IPv6-only hosts in the network with IPv6-IPv4 translation at the
edge. Others are using dual-stack hosts with IPv6-only routers in
the core of the network, and IPv4 tunneled or translated through them
to dual-stack edge routers. Still others are using native dual-stack
throughout the network, but that generally persists as an interim
measure: adoption of two technologies is not the same as
transitioning from one technology to another. Finally, some walled
gardens or isolated networks, such as management networks, use
IPv6-only end-to-end.

Again, knowing that there is such variance highlights a problem but does
not offer insight into dealing with it.

It is impossible to predict with certainty the path IPv6 deployment
will have taken when it is complete. Lessons learned so far include
aligning costs and benefits (incentive), and ensuring incremental
benefit (network effect, or backward compatibility).