IPv6 Confusion

Carl Rosevear Carl.Rosevear at demandmedia.com
Tue Feb 17 16:59:28 UTC 2009

So, I understand the main concepts behind IPv6.  Most of my peers understand.  We all have a detailed understanding of most things IPv4.  I have Googled and read RFCs about IPv6 for HOURS.  That said, to quickly try to minimize people thinking I am an idiot who asks before he reads, I need some answers.  First of all, several of my friends who feel they are rather authoritative on the subject of things network-related have given me conflicting answers.  So what's the question? ...

How does IPv6 addressing work?

I know it's been hashed and rehashed but several orgs I am associated with are about to ask for their allocations from ARIN and we are all realizing we don't really know how the network / subnet structure trickles down from the edge to the host.  We really don't have a firm grasp of all of this as there seems to be multiple options regarding how many addresses should be assigned to a host, if the MAC address should be included in the address or if that is just for auto-configuration purposes or what the heck the deal is.  There are a lot of clear statements out there and a lot that are clear as mud.  Unfortunately, even when trying to analyze which RFC superseded another.  Can I just subnet it all like IPv4 but with room to grow or is each host really going to need its own /84 or something?  I can't see why hosts would need any more addresses than today but maybe I'm missing something because a lot of addressing models sure allow for a huge number of unique addresses per host.

My buddy and I are about to go to Barnes and Noble, not having and luck with standard internet media but then we realized...  how will we know if any of that is really what we are looking for either?

>From what I can tell, this may still be a question of great debate.  Everyone seems to act like they know exactly what's going on but behind closed doors admits that they don't really know x, y, or z.  I realize this is typical of my industry and even myself from time to time.  J

But so I am truly reaching out here.  What is the deal with IPv6 addressing and subneting? Where is the official guide to this new galaxy?  I will be sure to pass this information on to my equally less clueful peers to the benefit of all of us that are making this transition.

There are people here at my company that seem to get it but can't seem to explain it clearly to me.  To me, its basically just larger addressing space with some new logical boundaries....  But there are so many discussions of potential addressing methods that I am confused.   I know from my lab setups that I can "make it work" but I'd like to "do it right".  J

I've been doing this for over 10 years now...   IPv4 is native to me.   If you can point me in the direction of some good, authoritative information or even say "Dood, go get IPv6 for dummies", that's fine I just need to know where to find some good information.

Can someone say "well, you know how it would be nice to have like 100 different addresses on hosts to differentiate services and blah blah....  Well now that's what you account for and so then you know how a /24 almost always ends up being tight in IPv4?  Right, so think of your basic bit boundaries that you adhere to as /?? And /???   In IPv6."   Or "Throw all that old thought out the window.    Now its kind of like how the Ford Probe is actually a Mazda...  ummm....  Yeah I can't really explain it either but it makes sense.  Here read this book and it'll make sense to you too."

Respectfully yours,

Carl Rosevear

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