[c-nsp] IPv6 Unique Local Address Routing Issue

[Phil Mayers]

On 09/10/2012 10:45 PM, Aled Morris wrote:
> On 10 September 2012 21:56, Mack McBride <mack.mcbride at viawest.com> wrote:
>
>> If you are using ULA please be sure to use the correct procedure to
>> generate a /48 and register the /48 subnet with SixXS.  This keeps ULA
>> unique.
>>
>>
> Am I the only one to find this a bit of a contradiction in terms?  If
> you're going to register it, how is it not then a kind of GUA?  Really?

Because it's not globally routable?

As I understand it, ULA are designed to solve the problem of a stable, 
internal-only address range that won't overlap in the cases where you 
might have to introduce links between networks - such as mergers and 
acquisitions, site-to-site VPN/extranet applications, and so on. Hence 
the random prefix assignement algorithm.

Given the algorithm, I have to question the value in additonally 
registering them. But registering them doesn't make them GUAs, and 
doesn't (I guess) do any overt harm.