Open Stack

Hey, all.  I have a Liberty cloud, and decided for the heck of it to 
start dipping my toe into IPv6.  I do have some confusion, however.  I 
can choose between SLAAC, DHCPv6 stateful and DHCPv6 stateless -- and I 
see some writeups on what they do, but I don't understand what 
differentiates them.  As far as I can tell, they all do pretty much the 
same thing, just with different pieces doing different things.  E.g., 
the chart, found here 
(http://docs.openstack.org/liberty/networking-guide/adv-config-ipv6.html 
-- page down a little) shows those three options, but it isn't clear:
* How to configure the elements involved
* What they exactly do (e.g., "optional info"?  What's that?)
* Why there even *are* different choices.  Do they offer functionally 
different results?

Any pointers would be much appreciated.  While I was able to get a host 
up with IPv4/IPv6, I wish I understood more of what was going on behind 
the scenes.

Thanks!

-Ken