Quoting RFC2860 [Re: I-D Action:draft-azinger-scalable-addressing-00.txt]

[Fred Baker]

On Sep 27, 2010, at 9:33 AM, Tony Li wrote:

> Certainly if someone is running a v6 network that is not Internet connected, then they are welcome to do whatever they like.  ;-)

I actually disagree. In the Smart Grid world, there have been suggestions that they use IPv4 and simply re-use the IPv4 address space "because the networks will never be connected". You can guess my response to that - "been there, done that, note the road rash". I think that they should operate as though they might eventually become connected, in part to deal with stuxnet-style issues and in part in case they inadvertently or intentionally become connected at some point in the future.