ISP customer assignments

[jfbeam at gmail.com (Ricky Beam)]

On Tue, 06 Oct 2009 17:40:40 -0400, Mark Smith  
<nanog at 85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org> wrote:
> I think it is both "classless" and "classfull" (although it's different
> enough that we probably should stop using loaded IPv4 terms ...)

It's _classless_.  There's none of this Class A, B, C, D, or E nonsense.   
The word everyone is dancing around is, "hierarchical".  How the bits get  
divided up depends on what you want to do with it.  SLAAC, in it's current  
form, requires a 64-bit prefix, but there are other ways to assign  
addresses that do not have that requirement.

--Ricky