IPv6 Address Planning

[James]

On Tue, Aug 09, 2005 at 03:10:50PM -0600, Cody Lerum wrote:
> The idea was to stay on a boundary for ease of subnetting, as well as
> provide aggregation via /112's within /80's.
> 
> /64's are possible, but will require burning a /48 for each Distribution
> site, and I was trying to reserve /48 level assignments for downstream
> organizations. While also only utilizing a /48 for my organization.
> 
> Seemed to make sense to me, but this is my first run at a v6 addressing
> plan.
> 
> -C 

Honestly, /112 vs. /64 to me is just "do whatever is comfortable for you and
your team the most" issue.  At first one can do a design that will take into
consideration of aggregation in routing as much as possible, but at the end of
the day, in my experience, route aggregation at least in my internal iBGP and
IGP table do not seem to be causing too much scalability problems than
expected, that just assigning /64s in a clean manner is simpler for us..

One can also say, "why not use /126 if you are really going point to point?"
To me, personally (and this is just me by the way), a /126 makes more sense
than a /112 for PTP links.  But by the same token, given that "/64 is what is
considered a subnet in IPv6" tradition still remains popular, we still remain
to use /64s at this time.  I guess it does not hurt to reserve another /48
for switchover to /126 if need be in the future ;)

James

> 
> -----Original Message-----
> From: Sander Steffann [mailto:steffann at nederland.net] 
> Sent: Tuesday, August 09, 2005 2:57 PM
> To: Cody Lerum; ipv6-ops at lists.cluenet.de
> Subject: Re: IPv6 Address Planning
> 
> Hi,
> 
> > Within these /80's are individual /112's for PTP links.
> 
> Why use a /112 for point-to-point links? The only reference I can find
> is rfc3627, and that one does not really seem to advise to use a /112
> except when using a /64 is not possible... So I am curious about why a
> /112 is used.
> 
> Thanks,
> Sander.
> 

-- 
James Jun
Infrastructure and Technology Services
TowardEX Technologies
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