Re: IPv6 Address Planning

[bmanning () vacation karoshi com]

On Wed, Aug 10, 2005 at 09:26:08PM +0200, Iljitsch van Beijnum wrote:
> On 10-aug-2005, at 19:32, bmanning () vacation karoshi com wrote:
>
> >    so renumbering out of a /56 into a /48 is harder than renumbering
> >    out of a /124 into a /112 how?
>
> Having a /60 or a /48 is better than a /56 or a /48 because:

        we are not talking better/worse, we are talking the 
        issues with renumbering... and the only credible argument
        you make is...
> 1. Most people who are going to encounter the problem realize that a / 
> 60 isn't enough and go for the /48 immediately
> 2. Going from a /60 to a /48 would happen earlier than from a /56 to  
> a /48 so there is less to renumber.

        less to renumber.  which argues that folks should be given
        just the amount of space they need, not more.  right?  :)


> >    renumbering - regardless of version
> >    is hard...
>
> Not hard, inconvenient.

        inconvient/hard ... regardless of versioning (v4 or v6)
        it is not trival to renumber a network that is managable.

> >    primarly becuase application developers insist that
> >    the IP address is the nodes persistant identifier,
>
> Disagree. There are two issues: the DNS and access restrictions and  
> similar based on IP addresses. The DNS can be fixed with some  
> searching and replacing and/or dynamic DNS updates, but using literal  
> IP addresses, especially in filters and such, isn't easy to solve  
> because there are no reasonable alternatives in many cases.

        ok, you disagree. clearly we do not have the same understanding
        of global networks, end-system configuration and maintaince,
        and the demand for reliable, auditable logs. 

> >    renumbering hosts is a breese in either
> >    version of predominate IP protocol, DHCP is your friend.
>
> That friend will kill all your sessions when you get a new address.  

        Sniff.  Tear.  your DOA w/ IPv6 as well and IPv4 in a
        renumbering event.  You want to maintain session awareness
        over a renumbering event?  IPv6 is not going to help.  You 
        need HIP.

> DHCP implementations in IPv6 aren't ready for prime time either.

        that statement could be made of so many applications. 

> >    Or if you
> >    want less robust functionality and semantic overload, you can use
> >    the RA/ND stuff in IPv6.
>
> How is that less robust and does it imply a semantic overload?

        DHCP is a protocol that has a long interoperability history.
        RA/ND does not.  DHCP has many fine host configuration features
        .. some of which are being added to the RA/ND suite.  Hence my
        claim of less robust.  Semantic overload... hum... I want my 
        router to route.  infrastructure services should come from service
        boxes...  in much the same way i want the police to direct traffic,
        not do my produce shopping, then take the goods home and prepare my
        meals.  The police should do police work, routers should route.

        YMMV of course.  Some people LIKE running their router, RA/ND, DHCP,
        and DNS, NTP, and WEB server off a single platform.  Or due to cost
        constraints they "bundle-up"...  I'm of the opinion that functional
        seperation is a good thing in the provisioning of network services.

> >  - regardless, renumbering from one address
> >    range to another is painful - CIDR -might- be helpful, but  
> > artifical
> >    constraints e.g /64 only serve to confuse.
>
> I agree. All boundaries between different parts of the address must  
> be flexible. That includes the boundary at the end of the address.  
> But I guess we have to save something for IPv7.       
        
        IPv7, IPv8, and IPv9 are all registered w/ the IANA.
        then IPX is a Novell trademark so i think the next step
        would have to be IPv11..

--bill