Ricky Beam jfbeam at
Tue Dec 3 02:35:28 UTC 2013

On Mon, 02 Dec 2013 20:56:13 -0500, Leo Bicknell <bicknell at> wrote:
> - A /56 is horribly wrong and the world will end if we don't fix it NOW.

I'm reminded of the Comcast trial deployments.  Wasn't their conclusion  
(with a collective thumbs up from the networking world) to go with /56?   
Yet, even they are handing out little old /60's.

> I would love to know what number of home users need 256 subnets.  The  
> good news is that folks doing DHCP-PD will be able to report on how many  
> people request all 256 networks available, and are thus "out".  In fact  
> they can make a histogram from 1 to 256 networks per household, and show  
> us how many request each number of subnets.

It doesn't work that way.  Routers aren't asking for individual prefixes  
('tho I suppose it's possible.) They ask for a /60 or /56, and then assign  
the space as necessary.  Thus, the ISP has no idea how many /64's are  
actually being used.

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