IPv6 has been discussed for many years. Ten years ago I remember working with an equipment manufacturer, now part of Alcatel-Lucent, that was moving into the IP business. One of their concerns was how to handle the migration to IPv6 for their carrier clients. Our discussion ended with the reality that IPv6 was a potential future concern, but the more immediate concern was for them to build credibility in their client-base with IPv4, it was not likely that IPv6 would be an issue for them for many years to come. The advent of CIDR and NAT had eliminated the immediate concern of address depletion.

Last month the American Registry for Internet Numbers (ARIN) stoked the fires for migration to IPv6. ARIN is now actively recommending the migration to IPv6 for anyone wanting large contiguous address blocks. They stated:

The available IPv4 resource pool has now been reduced to the point that ARIN is compelled to advise the Internet community that migration to IPv6 is necessary for any applications that require ongoing availability from ARIN of contiguous IP number resources.

Network World reported on the issue last week. An opposing view is presented by Dan York on his blog.

The big issue remains the need for a compelling argument for the move. Asia is moving to IPv6 much faster than the US. The move there is driven by the lack of addresses allocated to this fast growing market. In the US the government, led by the DoD, is also migrating to IPv6. However, there is no compelling reason for most businesses to migrate, in fact, there are reasons to not migrate. Vista is reported to have some issues with IPv6, network management tools are not readily available and allowing tunneling to have IPv6 and IPv4 coexist can create some security issues. Ten years on, I am still of the opinion that IPv6 is still a niche protocol, albeit one that is gaining momentum. Large scale migration is still years away for most corporations as the cost still outweighs the benefits for most networks.